The surviving suspect in the Boston Marathon bombings has been moved from the hospital to a federal prison 40 miles away that provides specialized medical care, the government said Friday.

Dzhokhar Tsarnaev was moved from Beth Israel Deaconess Medical Center, where he has been held and interrogated since his capture last week, to the federal prison at Fort Devens, Mass., the Marshals Service said.

Elise Amendola / AP

Devens Federal Medical Center is seen in Devens, Mass., in 2011.

The prison’s website describes it as a facility for men who need specialized or long-term medical or mental health care.

The most prominent inmate there is Raj Rajaratnam, who in 2011 was sentenced to 11 years in prison for insider trading. He has diabetes, and the prison has a dialysis center.

The prison is in a wooded setting on a military base that was decommissioned in 1996. Another inmate there is Sabri Benkahla, who is serving 10 years for lying to authorities about training with militants in Pakistan. Benkahla was accused of being part of an American group that trained with paintball guns. He is scheduled for release in 2016.

Roger Stockham, a Southern California man who was accused in January 2011 of plotting to blow up a mosque outside Detroit, served at Fort Devens and was released late last year. Stockham has a long criminal history that includes holding a psychiatrist hostage, kidnapping his son, trying to hijack a plane and threatening to kill the president.

A lawyer who has had clients sentenced to Fort Devens told The Hartford Courant in 2005 that the prison has an outdoor basketball court. Crafts, including woodworking and making leather goods, are popular, the lawyer told the newspaper — though it is not clear how restricted Tsarnaev will be.

At the time, a judge had recommended that John Rowland, a former Connecticut governor who pleaded guilty to a corruption charge, be assigned to Fort Devens. Instead he served about 10 months at a federal prison in Pennsylvania.

In 1918, during a flu pandemic that killed tens of millions of people around the world, there was a severe outbreak at what was then known as Camp Devens — a ghastly scene of piled up corpses and cots overflowing onto porches.

The outbreak came in the last days of World War I. According to an account published by the Johns Hopkins School of Public Health, men at Devens were so sick that their oxygen-deprived skin turned deep blue.

The decision on where to send federal inmates is made by the Bureau of Prisons, which does not generally disclose its reasons for assigning prisoners.

Boston police could be seen early Friday leaving the hospital, which has treated not just Tsarnaev but people injured in the marathon blasts April 15.

Tsarnaev, 19, was upgraded earlier this week to fair condition from serious. His injuries, including a gunshot wound to the head and neck that may have been self-inflicted, were so severe that he initially communicated with investigators by moving his head and in writing.

He also has injuries to the leg and hand, apparently from a firefight with police in suburban Watertown, Mass., on April 19 that played out about 12 hours before Tsarnaev was captured hiding in a boat parked in the driveway of a house.

New York authorities said Thursday that Tsarnaev had improved to the point that he could talk, and that in a second round of questioning he admitted that he and his brother decided on the run to carry out a second attack in Times Square. His brother, Tamerlan, was killed after the shootout.

Tsarnaev has been charged with federal crimes including conspiring to use a weapon of mass destruction, and Attorney General Eric Holder could decide to seek the death penalty.

Tsarnaev has told investigators that he and his brother acted alone when they built and detonated two pressure-cooker bombs near the finish line of the marathon. Three people were killed in the attack and more than 200 injured.

Dzhokhar Tsarnaev told investigators that the brothers were motivated by a desire to defend Islam after the American-led wars in Iraq and Afghanistan.

In prison, experts have said, Tsarnaev will probably be subject to special administrative measures that could sharply curtail his contact with fellow prisoners and the outside world. Stephen Huggard, a former Boston federal prosecutor who worked on the Sept. 11 investigation, said Tsarnaev’s parents, who are in Russia and have insisted he’s being framed, may not be allowed to visit.

Slideshow: Aftermath and reaction following Boston bombings

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Heightened security, empty streets, and memorials mark the the days after the Boston Marathon bombings.

Launch slideshow

At a hospital court room hearing earlier this week, Tsarnaev showed little sign of fear or remorse and his heart monitor didn’t register a blip when he was told he could be could be facing the death penalty, according to a source familiar with the events inside the room when he was read his rights.

The mother of the Tsarnaev brothers insisted Thursday that her sons are not responsible for the attack and said she did not see any aggression in the older brother, even when the FBI questioned him two years ago.

Speaking to reporters in Russia, Zubeidat Tsarnaeva also said the elder son, Tamerlan Tsarnaev, came to Russia for six months last year to attend a family wedding, visit relatives and later renew his Kyrgyzstan passport.

“America took my kids away from me,” she said. “I’m sure my kids were not involved in anything.”

U.S. investigators have said they want to know more about why Tamerlan Tsarnaev was in Russia. When he returned to the United States in July, he began posting radical Islamic videos to his YouTube account.

Matthew DeLuca of NBC News contributed to this report.

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This story was originally published on Fri Apr 26, 2013 7:18 AM EDT

The brothers suspected in the Boston Marathon bombings may have been headed for New York to party after the attack, the New York police commissioner said Wednesday.

“There was some information that they may have been intent on coming to New York, but not to continue doing what they’re doing,” Kelly told reporters at police headquarters. “The information that we received said something about a party, or having a party.”

A man authorities say was carjacked by the brothers has told investigators he believes one of the brothers said “Manhattan” before he escaped, but investigators have cautioned that it may have been a language mixup because the brothers were speaking with Russian dialects.

The surviving brother has told investigators that the pair acted alone, were inspired by an al Qaeda propaganda magazine, and plotted the bombing to defend Islam after the U.S.-led wars in Iraq and Afghanistan, federal law enforcement officials told NBC News.

Tamerlan Tsarnaev was killed early Friday after a shootout with police in the Boston suburbs. His younger brother and alleged accomplice, Dzhokhar, is in fair condition at a Boston hospital. The brothers killed a campus patrol officer and carjacked an SUV before the shootout, authorities have said.

Homemade explosives and one semi-automatic handgun believed to belong to the brothers were recovered by investigators, officials said. The gun’s serial number was obliterated, but Massachusetts state police were working to reveal the number.

Slideshow: Aftermath and reaction following Boston bombings

Cj Gunther / EPA

Heightened security, empty streets, and memorials mark the the days after the Boston Marathon bombings.

Launch slideshow

Cambridge police, meanwhile, released a booking photo of Tamerlan Tsarnaev from a 2009 domestic violence arrest during which he was accused of assaulting his girlfriend.

In a closed-door session on Wednesday, members of the House Intelligence Committee were briefed by the FBI and other federal agencies on the ongoing investigation. Among the issues discussed is what federal authorities knew about Tamerlan Tsarnaev's trip to Russia as well as a timeline on his radicalization. 

Also, according to an interview with Rep. Dutch Ruppersberger, D-Mich., the ranking member on the committee, it was learned that the device used to trigger the explosives was a remote control for a toy, not a cellphone as thought earlier.

Nine days after the twin blasts near the marathon finish line, authorities early Wednesday reopened the section of Boylston Street in central Boston where the first bomb went off.

The site of the explosion has been paved with fresh cement and is surrounded by orange construction cones but opened to foot traffic. People stopped to pay respects and take photos.

“The people of Boston are strong like cement. Strong people. They get together when it’s needed,” said Robert Bibias, a city masonry worker who early Wednesday cemented over what had been a blood-stained crime scene.

Thousands of people, including police from all over the country, gathered at the baseball stadium of the Massachusetts Institute of Technology for a memorial service for Sean Collier, the campus patrol officer who authorities said was shot to death by the Tsarnaev brothers before the carjacking and shootout.

With police snipers holding positions atop nearby buildings, Vice President Joe Biden called the perpetrators of the marathon bombing “twisted, perverted, cowardly, knockoff jihadis.”

“The irony is, we read about these events, we experience them, but the truth is, on every frontier, terrorism as a weapon is losing,” he said. “It is not gaining adherents.”

Tamerlan Tsarnaev is seen in a booking photo from a 2009 arrest in Cambridge, Mass.

The vice president went on: “We will not hunker down. We will not be intimidated.”

His wife, Dr. Jill Biden, visited Boylston Street on Wednesday.

Private funerals were held Tuesday for Collier and for Martin Richard, the 8-year-old boy killed near the finish line. Two other people were killed at the marathon, and more than 200 were injured, including 39 who were still hospitalized Wednesday.

In Russia, the brothers’ aunt said that a Boston-area mosque has refused to hold a funeral for Tamerlan Tsarnaev.

American authorities have told the family that they can have Tsarnaev’s body, and an uncle approached the mosque to request a burial and funeral but was declined, said the aunt, Patimat Suleimanova.

She said that she did not know the name of the mosque but that it was one the family attended. A mosque in Cambridge, Mass., has said that Tsarnaev attended and occasionally caused disruptions and that mosque leaders threatened to kick him out.

A spokesman for the Cambridge mosque, Yusufi Vali, said the mosque had not heard from the family.

“There were some reports out there that we had rejected his burial, and — or the family had reached out to us, rather. And to our knowledge, you know, the family has not reached out to us,” he said on the MSNBC program “Andrea Mitchell Reports.”

The mosque, run by the Islamic Society of Boston, has also said that congregants have been questioned by the FBI. The mosque did not immediately return a request for comment Wednesday from NBC News.

Earlier this week, Imam Talal Eid of the Islamic Institute of Boston, a separate institution, told The Huffington Post: “I would not be willing to do a funeral for him. This is a person who deliberately killed people. There is no room for him as a Muslim.”

NBC News' Adrienne Mong, Alastair Jamieson, Bill Dedman and Matthew DeLuca contributed to this report.

Related:

• Full coverage of the Boston Marathon tragedy
• Wife of dead bombing suspect in 'absolute shock'
• FBI quizzes members of mosque suspect attended

This story was originally published on Wed Apr 24, 2013 7:14 AM EDT

LONDON -- British authorities ordered more police on the streets for Sunday's London Marathon in the wake of the Boston bombings, but experts warned it was "virtually impossible" to guarantee the safety of the hundreds of thousands who will attend the event. 

A police source said additional patrols by uniformed officers were planned to reassure the public in the wake of deadly attack.

While British security officials have been in contact with their counterparts in the U.S. following Monday's blasts, the U.K.'s threat level for international terrorism hasn't been changed from "substantial" -- the third of five categories on the scale.

At least 500,000 spectators are expected to watch Sunday’s race and Prince Harry is due to hand medals to the winners.

The course takes the 36,000 runners right past major sites - including Tower Bridge, the Houses of Parliament and Buckingham Palace – as well as through Canary Wharf, the giant riverside financial district targeted twice by the Irish militants in the 1990s.

Even in a city that has spent recent decades under the threat of bombs – first from Irish Republicans, more recently jihadists – such a public event poses a security headache.

Sir Bernard Hogan-Howe, the commissioner of London's Metropolitan Police, said that the force was "taking more more precautions than we might have done otherwise."

"We will make sure we've got more officers on the street looking after people, making sure they're kept safe, but we've no reason to think they'd be any less safe than before the terrible events in Boston,." he said. "We'd be professionally irresponsible if we didn't take some reasonable steps."

Sang Tan / AP

Backdropped by Buckingham Palace, a jogger crosses the Mall in London on Tuesday. It will be transformed into the finishing area for Sunday's London Marathon.

Metropolitan Police Commander Christine Jones declined to give details of what changes might be made, if any, to the event's security plan. She said officers would “continue to review all the intelligence” available.

London Marathon chief executive Nick Bitel insisted the event would go ahead. “We will be reviewing our security in the coming days, in the light of what has happened in Boston," Bitel told ITV News.

"I don't want to talk about specifics of what security we have had in the past, or will have on Sunday. All I can say is that it will be of an appropriate level to meet whatever threat assessment is made, in conjunction with the police," he added.

Hugh Robertson, a British government minister, called for crowds and runners to attend in London as normal.

“The very best way to show solidarity with Boston is to get out there on the streets of London to cheer the runners on and to show that we won’t be defeated by this sort of activity,” he told the London Evening Standard newspaper.

Runners will be encouraged to wear a black ribbon at the start of the race to honor victims of the Boston bombing, and a 30-second silence will be observed, organizers said Wednesday. 

NBC News national security analyst Michael Leiter said it was “virtually impossible” to make a marathon completely secure because of its 26.2-mile long route.

“You just have to do the best you can to keep people safe and maintain resilience," he said. “It’s important we don’t alter our lives because that provides the terrorist – domestic, international, whoever it may be – with a huge victory.”

Helmut Spahn, executive director of the International Centre for Sport Security, told Reuters: "There has to be a clear analysis of the situation and certainly no over-reaction. More police, more military is not always the best solution. To have a 100 percent security is very, very difficult if not near impossible.”

Sang Tan / AP

A sign warns of road closures linked to the forthcoming London Marathon.

This story was originally published on Wed Apr 17, 2013 2:29 AM EDT

FBI.gov

The FBI released this image of two suspects in the Boston Marathon bombing case early on Friday.

The FBI released new photos of two "armed and extremely dangerous" suspects in the Boston Marathon bombing early Friday.

The pair — who were armed with explosives and guns — battled authorities in a Boston suburb until cops took one of the men into custody, and the other fled, sources said. Officials later said the the suspect taken into custody died.

The suspect seen wearing the white baseball cap in the photos was still on the run, according to officials.

Earlier, Boston FBI Special Agent in Charge Richard DesLauriers asked for tips, adding: "Somebody out there knows these individuals as friends, neighbors, co-workers or family members,"

"Though it may be difficult, the nation is counting on those with information to come forward and provide it to us.

"We consider them to be armed and extremely dangerous," DesLauriers added. "No one should approach them...If you see these men, contact law enforcement."

The images showed two men in baseball caps and dark jackets who were seen walking together through the crowd at Monday's iconic race. New headshots were released by the FBI at 2 a.m. ET on Friday.

Law enforcement sources tell NBC News that unreleased portions of the surveillance video show the suspect in the white hat working his way out of the crowd, then raising his arm to apparently lift the backpack off his shoulder, but the view is obstructed by others. He sets the backpack down, working his way out of the crowd, then pausing briefly just before the first bomb explodes. 

He then calmly begins to work his way away from the second device, sources said. Seconds later, the second bomb explodes, and a terrible scene of carnage is apparent.

Seconds after that explosion, a photograph now in hands of the FBI appears to show the suspect in the white hat moving away amid the smoke rising midway down the block behind him.

Two sources said they are looking for repeat names amid the flood of calls to the investigators’ tip line to give them leads on who the suspects are.

FBI.gov

This image, which was released by the FBI early Friday, shows two Boston Marathon bombing suspects together.

The man in the dark cap with a black backpack is being called Suspect No. 1. The other man, Suspect No. 2, is wearing a white cap backward and carrying a lighter-colored backpack.

The public was asked to call a hotline, 1-800-CALL-FBI, with tips or visit the bureau's website, bostonmarathontips.fbi.gov.

"No bit of information, no matter how small or seemingly inconsequential, is too small for us to see," DesLauriers said. "Each piece moves us forward toward justice."

Following the release of the photos, people had already started calling in names.

Investigators zeroed in on one of the men within the last day or so, he said. By examining photos and videos of the marathon crowd, they were able to identify a second suspect.

FBI

These are among the photos of the suspects in the Boston Marathon bombing released by the FBI.

"They appear to be associated," he said.

Massachusetts Gov. Deval Patrick echoed the FBI's call for the public to help. "Pass along to law enforcement any information about the suspects that you may have," he said.

The FBI released no other information about the probe, including the motive for the bombing, which killed three people, including an 8-year-old boy, and wounded 176.

Investigators are casting a wide net for clues. The FBI was canvassing hobby stores in the Boston area to determine whether electrical components in the bombs were bought there, NBC News learned.

Forensic work from the blast zone has helped authorities identify major components of the bombs.

They were housed in metal containers — at least one an everyday kitchen pressure cooker — and studded with metal, including fine nails or brads, to make the devices more lethal. A battery pack typically used on toy cars and a circuit board were also recovered.

FBI

The FBI is looking for these two men, identified as suspects in the Boston Marathon bombing.

But the videos are the biggest break in the case yet. They were unveiled hours after President Obama attended an interfaith prayer service to reassure both the injured and the city.

“You will run again,” he declared at the Cathedral of the Holy Cross, less than a mile from the finish line. “Your resolve is the greatest rebuke to whoever committed this heinous act.”

As of Thursday morning, 56 patients were still being treated in hospitals. That was down from 65 on Wednesday.

“In general, people are getting better, and we are happy with their progress,” Dr. Peter Burke, chief of trauma at Boston Medical Center, told reporters early Thursday.

The three people killed in the attack were Lingzi Lu, a Boston University graduate student; 8-year-old Martin Richard of Boston; and 29-year-old Krystle Campbell of Medford, a Boston suburb.

A trauma surgeon said that doctors have pulled fragments as large as 2 inches, including pieces of wood, concrete and plastic, from the bodies of the injured, in addition to metal shrapnel from the bombs.

NBC News’ John Bailey, Richard Esposito and Michael Isikoff contributed to this report.

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This story was originally published on Tue Apr 16, 2013 10:50 PM EDT

LONDON -- Former Boston Police Commissioner Bill Bratton said Tuesday that those responsible for the bombing of the city’s marathon should be put to death.

Bratton said he had “every confidence” that the authorities would “get to the bottom of this and bring those responsible to justice.”

Massachusetts abolished capital punishment in 1984, but Bratton said the federal authorities could take over the prosecution of terrorist acts like this and a federal court could pass the death sentence.

“I think this act would be an appropriate use of the death penalty as a penalty for the crime,” he said.

Bratton, who was born and raised in the city and policed its marathon for many years, said he was having dinner in the British capital when he started getting emails about the bomb blasts.

He spent the next few hours trying to find out what happened and whether people close to him had been hurt or killed.

“I’ve friends and relatives that would be at that event, some running in it, some observing,” Bratton said, adding that former police colleagues would also have been there providing security.

'No shortage of haters'
Bratton, who was also previously chief of the Los Angeles Police Department and New York's police commissioner, said there were a number of potential suspects, including al Qaeda.

“You line up the usual suspects and they’d certainly be at the front of the line, but unfortunately there’s no shortage of haters, people who don’t like the government … neo-Nazi types … any number of people are capable of wanting to participate and pull of this type of event,” he said.

But Bratton cautioned against anyone jumping to conclusions or indulging in “idle speculation” about who had carried out the attack and said people should allow law enforcement officers to deal with the investigation.

He said the authorities had been successful in preventing many terrorist attacks in the U.S., including "at least a dozen" in New York City, where he now lives.

Slideshow: Boston Marathon explosions

Charles Krupa / AP

See images from the scene of the explosions.

Launch slideshow

Bratton said this was partly down to good intelligence and "citizen observation." "If something looks suspicious, if you see something, report it," he said.

He admitted it was not possible to prevent every attack, but urged people to carry on with normal life despite the terrorist threat.

“You don’t let them create such a fear that you change the way you live,” he said. “We will move on. We will remember, we’ll commemorate, we’ll mourn, but life goes on."

However, speaking earlier on MSNBC's "Morning Joe," Bratton said the bombing would have a lasting effect. 

“I grew up in Boston. It [Patriots’ Day and the marathon] is an extraordinary day and one that I have great memories of," he said. "And those memories will be forever tainted.”

Related:

Full coverage of the Boston Marathon bombings from NBC News

Boston on high alert after marathon bombing kills 3, injures scores

Boston Marathon victims include two brothers who each lost a leg

FBI / AP

This image from a Federal Bureau of Investigation and Department of Homeland Security joint bulletin shows the remains of a pressure-cooker bomb that exploded during the Boston Marathon, the FBI says.

The FBI’s lead investigator into the Boston Marathon bombings on Tuesday made a passionate plea for information from the public, saying the “range of suspects and motives remains wide open” as the probe into who might be responsible for the attacks begins.

“Someone knows who did this,” said Richard DesLauriers, the special agent in charge of the FBI’s Boston office. “Importantly, the person who did this is someone’s friend, neighbor, coworker or relative. We are asking anyone who may have heard someone speak about the marathon, or the date of April 15, in any way that indicated that he or she may have targeted this event to call us.”

FBI / AP

The remains of a black backpack that the FBI says contained one of the bombs that exploded during the Boston Marathon.

DesLauriers told reporters in an afternoon briefing that the FBI has received more than 2,000 tips as of midday Tuesday, and investigators have already vetted some of those. In addition, many people and businesses have submitted photographs and video of the scene near the marathon’s finish line where the blasts occurred.

Still, investigators have no firm suspects in the case and no groups or people have stepped forward to claim responsibility for the attack that killed three people and injured at least 176.

“At this time,” DesLauriers said. “there have been no claims of responsibility.”

Federal prosecutors are preparing a limited number of search warrants in the Boston area in their search for evidence in the bombing, a senior federal law enforcement official told NBC News.

And, late Tuesday the FBI released photos showing contorted metal that it said were the remains of one of the pressure-cooker bombs used in the Boston Marathon attack. 

'Weeding through' evidence
Agents are "weeding through" the evidence, the official said. But the searches do not indicate that agents have any hard leads right now into who was behind the bombing, the official said, adding that the number of search warrants are "less than a half dozen."

More than a day after the bombs went off, crime scene processing continues with hundreds of hours of video simultaneously being viewed, a federal official said. At some point FBI behavioral profilers will join in the analysis, officials said, as they begin their effort to put together who the person or persons were who launched the attack.

Investigators have found fragments of dark or black nylon, which were possibly from a bag or backpack that contained the bombs. In addition, pieces of what is believed to have been a pressure cooker used in making the bomb have been discovered.

Those pieces of evidence, along with others, are being sent to the FBI’s lab in Quantico, Va., for testing to determine if they were indeed part of the bomb. The lab will attempt to reconstruct the explosive devices to determine their origin, DesLauriers said.

"This is a painful and tragic  lesson, but we will learn from this as well," said Massachusetts Gov. Deval Patrick.

Patrick also announced that President Barack Obama would attend an interfaith service honoring the victims of the tragedy at 11 a.m. on Thursday at Cathedral of the Holy Cross in South Boston. 

Sources involved in the investigation said late Tuesday that the pressure-cooker bombs were powerful "homemade claymore," directional explosives that appeared to include a triggering mechanism using a battery pack and a circuit board. Both of those elements were recovered at the scene.

"It appeared to be built from scratch but with a sophisticated triggering mechanism. And frankly, at the end of the day, all bombs are crude devices, and it is the way they are triggered that can be sophisticated," said one official with strong knowledge of explosives. "They functioned as designed."

According to a FBI-Department of Homeland Security document, a preliminary examination of photographs and on-scene reports show that one of the bombs consisted of a pressure cooker with an undetermined main charge. The other device was also housed in a metal container, but so far there is not enough evidence to determine if it was also a pressure cooker, the document stated.

The two Boston Marathon bombs appeared to have each contained tiny nails – smaller than the ones used to hang pictures, “fine nails” or brads, according to one of the people assigned to the case. And the devices themselves appear to have been delivered to the scene in two duffle bags.

'To the ends of the earth'
DesLauriers earlier vowed to go “to the ends of the earth” to find those responsible. But a day after the explosions, Obama said that authorities did not know whether the attack was foreign or domestic, the work of a group or an individual, or what the motive might be.

According to federal officials, there is no indication currently of any overseas involvement or direction in the attacks, and although the case is being handled by the international terrorism section of the FBI, that is simply a matter of resources, and if it turns out to be domestic the command of the incident will simply be switched.

Law enforcement officials told NBC News that the explosives were classified as low — meaning that they traveled at under 3,300 feet per second. That is not enough to create a blast wave, which can kill people from air compression and blow out faraway windows, but it is enough to propel shrapnel a great distance.

A pressure cooker, in its everyday use, speeds cooking by creating a tight seal and building pressure inside the pot. Converting it to a bomb sheaths the explosives in a metal casing, which blows apart when the bomb is detonated and adds to the shrapnel already packed inside.

Rep. Michael McCaul, R-Texas, chair of the House Homeland Security Committee, said that he knew of two ways to detonate a pressure cooker bomb — with a device placed on the cooker or by remote, such as by cellphone. Law enforcement could use records to track a cellphone detonation, he said. 

One of the three devices that was to be used in an attempted bomb attack in Times Square in 2010 was a pressure cooker. Earlier that year, terrorists used a pressure cooker bomb in an attack in Pakistan. And in 2006, more than 130 people were killed on the transit system of Mumbai, India, when pressure cookers loaded with explosives were placed on trains.

In the hunt for clues in Boston, informal public efforts sprang up almost immediately to scour the mass of photos and video already posted on Twitter, Facebook and other sites. Authorities added their own call for help, hoping that in an era of ever-present smartphones, race fans might be holding evidence without even knowing it.

Slideshow: Boston Marathon explosions

Charles Krupa / AP

See images from the scene of the explosions.

Launch slideshow

“There has to be hundreds, if not thousands, of photographs, videos and other observations that were made down at that finish line yesterday,” said Timothy Alben, superintendent of the Massachusetts State Police. “You might not think it’s significant, but it might have some value to this investigation.”

From the White House, Obama praised acts of heroism after the explosions and said that the investigation would take time.

Obama: 'We will bring them to justice'
“We will find whoever harmed our citizens, and we will bring them to justice,” he vowed. “We also know this: The American people refuse to be terrorized.”

Authorities confirmed at a mid-morning news conference that only two bombs went off Monday. Contradicting reports from the chaotic early hours after the blasts, they said that no unexploded devices were found.

Overnight, law enforcement officials searched a suburban Boston apartment building, interviewed a man and removed a duffel bag and two trash bags. But a law enforcement official later told NBC News that nothing of interest was found. They also issued alerts for a rental van and a man seen leaving the scene of the blasts.

Law enforcement officials also told NBC News that the bombs, which detonated seconds apart, were packed with ball bearings and BBs, apparently intended to increase the casualties. The blasts turned the finish line of the marathon into a hellish scene of panicked spectators, shattered glass and blood-spattered sidewalks.

Twitter

Martin Richard, 8, was killed in the marathon bombing.

Among the dead was an 8-year-old Boston boy, Martin Richard, who was waiting at the finish. Krystle Campbell, 29, of the Boston suburb of Medford, was also killed, her father told NBC News. The Chinese consulate in New York said the third victim was a Chinese national. The victim, whose family has requested she not be identified, was also a student at Boston University, the school said. 

As of 3:30 p.m. ET, there were 72 patients from the blasts still being treated at six Boston hospitals, including some who had injuries described as “limb-threatening.” An official at Boston Children’s Hospital said the youngest victim was a 2-year-old boy with a head injury.

Among the other injured were brothers, 33 and 31, who each lost a leg from the knee down. Dr. George Velmahos, chief of trauma at Massachusetts General Hospital, told reporters that surgeons had removed pellets, nails and other shrapnel from the bodies of patients. They bled heavily, and some required amputations, he said.

Investigators were studying surveillance video to look for anyone placing packages at the points where the bombs exploded. Law enforcement officials said there was video showing a person, from the back, carrying two backpacks, but they said it was too soon to know whether that was related to the attack.

The Boston police commissioner called the resulting crime scene the most complex that the department has ever dealt with, and said all sworn officers were working around the clock. The FBI took charge, but an array of law enforcement agencies joined the hunt. Leads poured in.

Investigators picked through mounds of personal belongings left by some of the thousands of people who fled the finish line, at Boylston Street, after gathering for perhaps the most joyous day on the Boston calendar — Patriots Day.

Authorities at all levels asked for patience. Sen. Dianne Feinstein, D-Calif., the chair of the Senate Intelligence Committee, said that she had great faith that an arrest would be made.

“I don’t think it’s going to be the day after tomorrow. But that’s OK. It’s going to happen,” she said. “You cannot do this in the United States.”

Public officials have repeatedly praised spectators, runners and race volunteers for charging in to help. One in particular gained online fame — a man named Carlos Arredondo who was pictured in a photo helping rush a gray-faced young man in a wheelchair to safety, pinching what appeared to be a protruding artery to stop the blood.

Do you know a Boston hero? Tell NBC News

Obama cited runners who had kept going after the race to get to hospitals, and people who tore off clothes to make tourniquets.

“If you want to know who we are, what America is, how we respond to evil, that’s it,” he said. “Selflessly, compassionately, unafraid.”

Gov. Patrick and Boston Mayor Thomas Menino said a new centralized fund was set up in order to to gather donations to help families affected by the tragedy. Called The One Fund Boston, contributions can be made through a website, onefundboston.org. 

Firefighters spent the night chasing bomb scares around a jittery city, and the country was on edge on the day after the explosions. A terminal at LaGuardia Airport in New York, a plane in Boston and part of the Cleveland transit system were briefly cleared because of suspicious packages. Authorities in big cities increased security.

A fire at the John F. Kennedy presidential library in Boston more than an hour after the blasts, initially treated by investigators as related, appeared be caused by a simple electrical short, police said.

The blasts went off just before 3 p.m., with thousands of runners still on the course. They sent up white plumes of smoke, rattled police barricades and stiffened flags set up to celebrate the 96 countries that sent runners to the most prestigious road race.

“In 28 years, this is definitely the worst I’ve seen,” said Chief Ron Harrington of the Boston Fire Department’s District 3. “Bodies and body parts. Blood all over. A little boy lying in the street. A young woman in her 20s. Both dead. It was mayhem. I saw two people with arms hanging loose, and one without a leg. A shoe with flesh still in it.”

Law enforcement officials told NBC News that authorities questioned a 20-year-old man who is in the United States on a valid student visa. He was seen running from the blast area, had burns and was interviewed in a Boston hospital. But an official told NBC News that interest in the man was fading. It was his apartment building, in the Boston suburb of Revere, that police and federal agents searched overnight.

The race drew 27,000 runners and has been run since 1897 on Patriots Day, the third Monday in April, which commemorates Lexington and Concord, the two battles in Massachusetts that started the American Revolution.

The year, the race coincided with the filing deadline for federal taxes. Security experts said the FBI would undoubtedly look into the possible significance of the date as they tried to find the bomber and the motive.

Michael Isikoff, Jeff Black, Jonathan Dienst and Michael Kosnar of NBC News contributed to this report.

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This story was originally published on Mon Apr 15, 2013 11:03 PM EDT

A Pennsylvania mall was evacuated Sunday after a bomb threat was written on a note found in a fitting room, according to police.

The note said there were multiple bombs at the Mall at Robinson in Robinson Township, Pa., just 12 miles outside downtown Pittsburgh. After combing through stores with bomb sniffing dogs, no explosives were found. 

The typed note, found at Sears, said the bombs would go off if not found, police told NBC's Pittsburgh affiliate WPXI. No specific time, store or reason was given.

The scene was officially cleared by police around 5:30 p.m. and the mall will reopen on Monday.

No arrests have been made, but investigators hope the note will provide clues as to who made the threat. Police have received an anonymous tip about a possible suspect, WPXI reports.

A pizza cook who admitted making a hoax call warning of liquid explosives on a plane, causing the flight to be diverted, must write an apology letter to every delayed passenger.

Kenneth Smith Jr., 26, pleaded guilty Monday to malicious false information about an explosive, and false information and hoaxes, according to a press release from the U.S. Attorney’s Eastern District of Pennsylvania Office.

The Philadelphia man's call to airport police led to US Airways flight 1267, bound for Dallas-Forth Worth, being diverted back to Philadelphia airport shortly after take-off on Sept 6.

Sixty-nine passengers and five crew members were on the plane.

Smith faces up to 15 years in prison and fines of up to $500,000 when he is sentenced on April 16. He has agreed to pay restitution and write an apology letter to every passenger who was on the flight when it was delayed, and reimburse the emergency response costs, prosecutors said.

Smith’s reasoning for the hoax, according to federal prosecutors, was to target a passenger on the flight, Christopher Shell, who was at the time identified as the ex-boyfriend of Smith’s girlfriend.

Reportedly Shell had posted a compromising photo of the woman on Facebook.

Shell was removed from the airplane in handcuffs. He later wound up making it to Dallas where we was arrested on two outstanding warrants, police said. NBC Dallas spoke to Shell in October about the plane hoax and how it derailed his career.

Traffic stands still near LSU's campus Sept. 17, 2012.

Students, professors and staff at Louisiana State University were allowed to return to the school’s main campus in Baton Rouge Monday night, hours after a bomb threat forced a full-scale evacuation, school officials said.

“All classes and events scheduled for Tuesday, Sept. 18 will be held as planned, and university employees and students should plan to return to their normal schedules on Tuesday,” LSU’s website said Monday night.

LSU Police and other law enforcement agencies are still investigating the origin of the threatening call.

Law enforcement officials had been on high alert since a call came in at 11:32 ET saying there was a bomb on the university’s grounds, university spokeswoman Christine Calongne said.

View the latest developments on breakingnews.com

Students and staff were sent text messages and an alert was posted on the campus website warning, "A bomb threat has been reported on the LSU campus. Please evacuate as calmly and quickly as possible."

Classes and a news conference with LSU football coach Les Miles were canceled Monday due to the threat, officials said. Students and staff were asked to stay off campus as the university investigated the bomb threat.

"It is important for all members of the LSU community -- faculty, staff and students -- to remain off campus unless specifically instructed to return," the university said on its website.

Capt. Doug Cain of the Louisiana State Police told The Associated Press that state police bomb technicians were on the scene. Cain said police were talking to their counterparts in both Texas and North Dakota where university bomb threats were reported last week.

Traffic was at a standstill as the main campus’s 30,000 students, professors and staff evacuated school grounds. Buses loaded with students barely moved from the central part of LSU’s campus, according to The Advocate in Baton Rouge.

Andrew Arceneaux, an LSU student studying business administration, joined other students and waited for buses to arrive so they could leave campus.

“I was in the middle of taking a test and they walked in and told us we had to leave campus,” Arceneaux told the Advocate.

Both the University of Texas in Austin and North Dakota State in Fargo received threats on Friday. The threats prompted the evacuation of both campuses. No explosives were found at either university.

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