Daniel Holmes for NBC News

Brittany Loring, right, and Liza Cherney, both of whom were seriously injured in the Boston Marathon bombings, lead the procession Monday at the Carroll School of Management commencement ceremony at Boston College in Chestnut Hill, Mass.

Before she was seriously wounded in the Boston Marathon bombings, Brittany Loring didn’t have to give much thought to her graduation walk.

But on Monday, after ditching the single crutch she had been using during her recovery, she walked with a stiff limp to collect her diploma from Boston College’s Carroll School of Management -- passing a “milestone,” she said, as she recovers from the horrible events of April 15. She was joined by a close friend, Liza Cherney, who was also hurt and was graduating from the program.

“This is the first step to overcoming it," Loring told NBC News before the ceremony. "It’s definitely showing that the individuals that committed this crime are not holding me back. At least in terms of the goals that I had prior to the event and post event, they haven’t changed.” 

Loring, who earned an MBA degree on Monday, was cheering on friends in the city’s iconic road race as part of her 29^th birthday celebration when the bombs exploded. She suffered a skull fracture and concussion, was struck by BB pellets -- including one in the neck and two in the head, and had wounds on both of her upper thighs, likely from shrapnel.

After three surgeries to clean and close the wounds, and weeks of occupational and physical therapy, Loring managed to walk for the first time without crutches last week, lasting as long as 15 minutes. She also has begun to venture into crowds again, a daunting prospect for some of the injured, and resumed some of her routines, such as visiting a local café. 

“I feel better every day," she said, noting she can now bend her knee to 90 degrees. "I seem to be moving pretty quickly in comparison to where I started.”

Loring’s classmates at Boston College, where she will also receive her law degree on Friday, sprung to action in the aftermath, making sure she wasn’t alone and was getting the care she needed. Cards, meals and flowers also streamed in.

“I knew that I had a tight group of friends … but I mean there is nothing like an event like this to really give people the opportunity to show how much they care,” she said. “After this event I just, I feel a lot closer to them … and I can see how much they respect and care for each other and for me.” 

Boston College said it waived Loring’s final exams and last assignments so she could graduate with her class.

On Monday, Loring walked alongside Cherney, who said she was struck by a lot of shrapnel in one leg. The friends bore big smiles under sunny Boston skies. 

Daniel Holmes for NBC News

Brittany Loring receives her diploma Monday.

“I expect that we will be friends forever," Loring said. "We’re really close and I’m so happy that she’s doing as well as she is and that we will be able to move forward and carry on.” The shared walk in the ceremony “definitely has a lot of meaning for me,” she added.

Though it was such an accomplishment to achieve the MBA, Cherney said the day took on greater significance after the attacks.

"It is more special because I feel very close to so many people who are graduating with us today, even closer than before,” she told reporters after the ceremony.

The pair was among 275 injured in the attacks. Loring will join some of the injured at a local rehabilitation hospital later this week, where she will do outpatient therapy. Eighteen people remain hospitalized after the bombings as of Friday.

"I’ve been trying to get things back to normal and that’s not always easy," Cherney said. "Just seeing that you can’t do things that you used to be able to do as easily has been a struggle. And also, I mean, from an emotional standpoint every once in a while it’s tough, but I think that ... you’ve got to push through.”

Doctors haven’t given Loring a time frame for a full recovery, but she plans to walk in her wedding in September and to start her job in international tax in October.

Reflecting on the attacks, she said she has had her ups and downs emotionally.

"It is life changing in some ways," she said. " ... but I hope that it will only be in a positive way, and that it will just make me a better person for it.  ... I hope that I will be able to do good in my life because of this understanding.”

To donate to Brittany Loring, her family has set up this fund. And for Liza Cherney, this fund.

NBC freelance photographer Daniel Holmes contributed to this report.

Related:

Marathon bombing victims adjust to a 'different normal'

Full coverage of the Boston Marathon tragedy on NBCNews.com

Scott Oxhorn

Children and their parents gathered in Dorchester, Mass., last weekend to paint a 100-foot-long banner in memory of Martin Richard, the 8-year-old boy killed in last week's bombings at the Boston Marathon.

BOSTON -- With song, brushes and buckets of paint, children in Boston are using the arts to try to express feelings about last week's marathon bombings for which even their parents do not have words.

"Painting for Peace” was inspired by 8-year-old Martin Richard, the youngest person killed in the attack near the finish line of the Boston Marathon. Parents and their children turned out last weekend in Dorchester, Mass., the Richard family's home, to paint a 100-foot-long roll of wallpaper with swirls of color and the message held up on an art project by the gap-toothed boy in a picture that went around the world last week: "No more hurting people. Peace."

"It was just the most obvious message that was on everybody's minds," said Liz Carney, who organized the project with her group Dot Art. "We were seeing that image and that message everywhere. A message about peace had a really important place in our response, in our community."

The sign now greets drivers passing under the Savin Hill Bridge over Interstate 93 heading into Boston. About 25 to 50 volunteers of all ages showed up to help create the banner, cards and other paintings and drawings over the weekend, Carney said.

"It was really a very heartfelt expression of peace and solidarity by our neighborhood," Carney said. "I had a lot of parents say how grateful they were to bring their kids to be a part of it, that the children in our community sometimes need a place to express things that are beyond words, and using their hands and having a place to tangibly put their energy is really important."

Boston-area children have turned to art projects like this one in Dorchester to help heal the wounds left by last week's marathon bombings.

Martin Richard’s sister Jane, 7, is among the 425 children from across the city who take singing lessons with the Boston City Singers. Not all of the youngest singers know all the details about the deadly blasts, but they know Jane was among the more than 260 people injured in the attack. Jane Richard lost a leg in the explosions; the children's mother, Denise, was seriously injured.

When a group of 4-to-6-year-old singers went back to Boston City Singers on Wednesday, parents were invited to stay if they wanted, managing director Melissa Graham said. Everything went well even when one little boy had a question about their missing classmate she said.

"One little boy said, 'Janie got hurt, is she going to be OK?'" Graham said. "And the conductor said, 'Yes, Janie is going to be OK. That was just an accident. Janie got hurt, she is going to be OK.'"

Boston City Singers charges tuition but does not turn away children on a financial basis, and makes up for costs with fundraising and grants, Graham said. The same way the children forget about whose parents have more money while making a song together, she said, maybe they will forget about the bombings for a little while when the youth choral group performs at "Children Sing for Peace" on Saturday at St. Mark Church in Dorchester.

The concert, which includes the Cambridge Children's Chorus and other local singing groups, will be about community and not about the bombs allegedly set off by brothers Tamerlan and Dzhokhar Tsarnaev. Other singers will come from the local Neighborhood House Charter School, which Jane and Martin attended and where their mother works.

"Song is one of those things that unites people," Graham said. "It gives the community a chance to feel like they are doing something."

The same need for expression was clear to Margery Buckingham when children came into the Dorchester Arts Collaborative on Tuesday. She said the week of arts and crafts she had planned for the 8-to-12-year-olds would not continue as though nothing had happened.

"One little girl said how she didn't sleep all night because she was so frightened," said Buckingham, education director at the collaborative, which fosters the arts in Dorchester.

Heidi Katz, an arts therapist from nearby Roxbury, Mass., came in on Thursday, Buckingham said. She did drawings and spoke with the children, and brought rhythm instruments for them to play. She asked the children where they felt safe.

"With most of our children it was at home and in church," Buckingham said. "And one little girl said, 'In my heart.'"

Buckingham called parents to let them known beforehand that the arts therapist would be coming, in case they did not want their children to participate. All the children showed up, and parents sent two more.

"It's something we have to do again," Buckingham said. "These feelings aren't going to go away."

Related stories:

• Source: Bombing suspect showed no fear or remorse during hospital hearing
• Mother of Boston suspects insists sons not responsible
• Family connections can be key in journey down terrorism path
• Full coverage of the Boston Marathon tragedy from NBC News

Courtesy Alyssa Loring

New England Patriots' running back Stevan Ridley and tight end Rob Gronkowski visited Brittany Loring on Monday in her hospital room and signed a jersey for her. Loring suffered multiple injuries in last week's bombing at the Boston Marathon.

BOSTON – Nine days after the Boston Marathon bombings killed three people and injured more than 260 others, at least one survivor is on the long road to recovery.

Brittany Loring, who was celebrating her 29th birthday last Monday when the bombs went off, suffered serious damage to her left leg in the twin explosions allegedly carried out by brothers Tamerlan and Dzhokhar Tsarnaev – who lived less than a mile from Loring and her fiancé, John McLoughlin, in Cambridge, Mass.

Wounds reveal part of the damage: She was left with small pellet-sized wounds across her body, some red, others black. But she also suffered a cracked skull, a concussion, and had to endure three “cleaning” surgeries to help prevent infection from her shrapnel wounds, said McLoughlin.

In the immediate aftermath of the attacks, it wasn’t clear if she would be able to walk again. But that changed Tuesday.

“She's starting to walk on her crutches, still in a lot of pain, and on heavy medication,” her dad, Dan Loring, a 53-year-old real estate agent, said late Tuesday. “She's looking good. She actually wore clothes today and did her hair.”

McLoughlin has been keeping a constant vigil at Brittany’s bedside, taking leave from his work as a loan officer to focus on her recovery and spend time in what he quips is their “little hotel room.”

“She's half the team, so I've got to be here,” he said Wednesday. The couple plan to wed in September. “Her spirits are good,” he said. “She's still up and down, but overall she's better.”

Boston Medical Center said Wednesday her condition was fair. It's not clear yet when Brittany will leave the hospital, but when she does, she will need physical and mental health therapies, he said.

“She wakes up in the middle of the night. She has nightmares,” McLoughlin said. He believes they are all related to the bombings, but he hasn’t asked for details. “We wake up a couple of times a night. She's startled, and I try to get her back to bed.”

Her family hasn’t been speaking to her about the bombings and what happened at the finish line of the marathon.

David Friedman / NBC News

John McCloughlin (left) and Dan Loring talk about the injuries sustained by Brittany Loring in the Boston Marathon bombings. McCloughlin is engaged to Brittany and Loring is her father.

“We're not bringing that in at this point,” said Loring, of Lancaster, Mass. “We're trying to build up her stamina – you know she had three surgeries in six days and ... the heavy medication. So trying to get her to eat, think positive thoughts.”

“We have told her she's safe but that's it,” McLoughlin said. “We don't think it's good for her recovery” to talk about it.

Besides getting back on her feet again, Brittany recently had other good news: Boston College has said she will graduate this spring with a joint degree in business and law, waiving her final exams and some last assignments. 

“She's very strong. She'll move on. This will be a blip in the past,” McLoughlin said. “I hope a year from now we're all good.”

This story was originally published on Wed Apr 24, 2013 6:44 PM EDT

FBI via Reuters

Dzhokhar Tsarnaev is at Beth Israel Deaconess Medical Center now. The feds will have to figure out where he goes next while awaiting trial.

Boston Marathon bombing suspect Dzhokhar Tsarnaev has been hospitalized since his arrest, but if his condition continues to improve he will soon experience the hospitality of a high-security lockup while waiting for a trial that could be two years away, experts say.

"As soon as he is medically cleared, he'll be moved," said Steven Swensen, a former U.S. marshal who now runs a judicial security consulting firm. "This is a high-threat, high-profile situation."

Tsarnaev's condition improved from serious to fair on Tuesday. But his injuries -- including a gunshot wound to the head and neck that could be self-inflicted -- were so severe he initially communicated with investigators in writing.

The hospital and FBI have not released details of his treatment at Beth Israel Deaconess Medical Center, where he was under heavy guard, or given any hint of when he might be released.

When it happens, the U.S. marshals and federal prosecutors will have to weigh distance from the courthouse against security and medical needs in choosing a new temporary home for the suspect.

Federal prisoners are sometimes sent to the Plymouth County Jail, which can handle high-risk prisoners but does not have extensive medical facilities. The state's Shattuck Hospital has a jail unit and is only about 20 minutes from the courthouse.

Further afield, there's the Wyatt Detention Center in Central Falls, R.I., a privately run maximum-security federal detention facility less than an hour's drive Boston, or the federal prison hospital at Fort Devens in Harvard, Mass.

If it's Wyatt, Tsarnaev would be far from the first high-value prisoner locked up there. Rezwan Ferdus, who pleaded guilty to trying to fly bomb-laden model aircraft into the Capitol and the Pentagon, spent 399 days in solitary confinement at the facility before he was sentenced.

But the 771-inmate center has just four hospital beds, according to its annual report, and it became the subject of controversy in 2008 when an immigration detainee died of advanced cancer and the feds found he had been neglected.

Devens is a medical facility but doesn't typically house suspects before sentencing. The Bureau of Prisons said it can handle detainees of any security-risk level, but it's also about an hour from Boston.

Wherever he ends up, experts said, Tsarnaev will likely be subject to special administrative measures that could sharply curtail his contact with fellow prisoners and the outside world.

Elise Amendola / AP file

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

Stephen Huggard, a former Boston federal prosecutor who worked on the 9/11 investigation, said Tsarnaev's parents, who are in Russia and have insisted he's being framed, may not even be allowed to visit.

How long the University of Massachusetts-Dartmouth student spends in a local lockup depends in large part on whether prosecutors decide to seek the death penalty -- a decision that is months away and will ultimately be made by Attorney General Eric Holder.

If the marathon bombing becomes a capital case, it could be "a couple a years" before a jury decides his fate, Huggard said.

Tsarnaev, 19, hasn't even been arraigned yet.

He nodded answers to a few questions at a cut-and-dried initial appearance before a magistrate in his hospital bed after being charged with one count of using a weapon of mass destruction and a second count of malicious use of an explosive.

The next step is for a grand jury to vote on an indictment. Technically, prosecutors have 30 days to get that done, but legal experts agree the deadline is likely to waived by both sides while they continue to investigate.

The suspect's next court date, May 30, would then be a status hearing, and he would not be arraigned until the indictment -- which could contain more charges and evidence than the criminal complaint signed this week -- is issued.

"There is no reason to rush at this point," said Dan Collins, a former federal prosecutor in Minnesota who worked on the Mumbai bombing case.

Tsarnaev has been assigned three federal public defenders who are likely, given what legal analysts describe as overwhelming evidence, to open discussions about a plea deal that would keep their client off death row at the "supermax" prison in Terre Haute, Ind.

"It wouldn't shock me if this ends in a plea," Huggard said.

"This is a kid, and as heinous as his acts are, he acted atypically for what we would expect for a terrorist," he said, noting that Tsarnaev was back at school and the gym after the bombing and before the bloody rampage that led to his arrest.

"Does it mean he didn't fully comprehend what he was doing? That's going to get explored by both sides."

But Huggard added that if Tsarnaev was telling the truth when he reportedly told investigators he and his older brother Tamerlan were lone actors and not sponsored or deployed by a terrorist cabal, it may make it harder to get the death penalty off the table.

"Then he has nothing to offer," he said. "Then he's just a guy who decided he wanted to blow up America."

Related:

• Bomb suspects' phones, computers show no sign of accomplice
• Wife of dead bombing suspect in 'absolute shock'
• FBI quizzes members of mosque suspect attended

Just weeks before the Boston Marathon bombing,Tamerlan Tsarnaev — the suspected mastermind of the plot — was still attending prayer services at a Cambridge mosque where he had previously caused disruptions and been threatened with eviction, a spokesman for the mosque said.

Yusufi Vali, a spokesman for the mosque, said that FBI agents have begun questioning members of the mosque about their interactions with the 26-year-old Tsarnaev, who was killed during a shootout with police last Friday, and his younger brother, Dzohkhar, who is still hospitalized and has been charged with helping carry out the attack.

As soon as mosque leaders learned of Tamerlan Tsarnaev’s alleged involvement, “We immediately called law enforcement and said, ‘Listen, we’ve got folks who knew him and if you need any information, we’re here – and those folks have already met with the FBI.”

Read statement by the Islamic Society of Boston, operator of the mosque

Dzhokhar Tsarnaev has told investigators he and his older brother acted alone, learning how to build the pressure cooker bombs by reading the al Qaeda propaganda magazine Inspire online. He said they plotted the bombing to defend Islam because of the U.S. wars in Iraq and Afghanistan, federal law enforcement officials tell NBC News. 

FBI agents have also begun reviewing the two brothers’ cellphone and email records and so far have found no sign of accomplices -- or connections to international terror groups, said a counterterrorism source who has been briefed on the investigation. 

But there are signs that Tamerlan had become radicalized — apparently from a friend in the United States named “Mischa” — described as a Russian of Armenian descent who was a relatively recent convert to Islam and who lived in Cambridge, according by Tsarnaev’s uncle, Ruslan Tsarni. Tsarni told NBC News that Mischa presented himself as an “exorcist” who specialized in “removing demons from people’s bodies.” He recounted hearing from his brother, Anzor, Tamerlan and Dzhokhar’s father, about an incident in 2007 when the father came home one night and found Mischa lecturing his son about Islamic ways. The father was outraged and ordered Mischa to leave the house. Shortly after that, he said, Tamerlan dropped out of school, telling his parents that music and the arts were incompatible with Islamic teachings.

Ruslan Tsarni said he has told the FBI about Mischa. NBC News has been unable to contact him, and Vali said that he is unaware of anybody in the mosque community who matches the description.

FBI agents are also trying to determine if there were other influences on Tamerlan Tsarnaev from people he may have met with during a six-month trip to Russia last year — during which he spent time in Chechnya and Dagestan, according to his father.

After the trip, a YouTube account was set up filled with postings of radical jihadi videos — including the sermons of Feiz Mohammed, a radical Muslim preacher from Australia who has been investigated by authorities for allegedly inciting violence. Authorities in that country have examined a series of sermons known as the “Death Series,” in which he describes Jews as “pigs” and encourages Muslim parents to offer up their children as soldiers to defend Islam.

Vali said that, after Tamerlan Tsarnaev was identified as a suspect in the Boston bombing last week, congregants reported two incidents in which he had disrupted services at the mosque. The most recent one took place on Martin Luther King Day in January, when Tsarnaev interrupted a talk by a speaker saying King could be compared to the prophet Mohammed.

 Tsarnaev stood up and called the speaker a “non-believer” and a “hypocrite,” he said. At that point, “the congregation yelled back, ‘You need to leave.” And then leadership had a conference with him, and told him, that you need to stay silent or you are not welcome here.”

Vali said that Tsarnaev returned to the mosque — as recently as last month — but there were no further disruptions.

 Related stories

• Boston Marathon bomb suspect charged with using weapon of mass destruction
• Doctors: All remaining Boston bomb patients likely to live
• Cops who cuffed bomb suspect: 'No time to be afraid'

This story was originally published on Mon Apr 22, 2013 6:52 PM EDT

A mosque outside Boston said Saturday that the two brothers suspected in the bombing of the Boston Marathon were “occasional visitors” who never “exhibited any violent sentiments or behavior.”

The Islamic Society of Boston Cambridge Masjid said in a statement that its community was “in shock to have learned of the crimes of these individuals.”

People who knew Dzhokhar and Tamerlan Tsarnaev, the men authorities say set off twin blasts near the marathon finish line Monday, have been urged to call law enforcement and have done so, the mosque said.

Dzhokhar Tsarnaev was captured alive hiding in a boat outside a home in Watertown, Mass., and was in serious condition Saturday and under heavy guard at a Boston hospital. Authorities were waiting to question him and were preparing charges.

Tsarnaev was injured in a firefight with Watertown police early Friday that left his brother dead.

Federal authorities are trying to determine a motive for the attack, which killed three people and injured 176.

The FBI confirmed that it questioned Tamerlan Tsarnaev in 2011 for possible extremist ties after a tip from a foreign country that he was a “follower of radical Islam” and planned to join an underground group.

Agents talked to him and neighbors and did not find “any terrorism activity, domestic or foreign.”

The Islamic Society of Boston Cultural Center, the largest Islamic place of worship in New England, closed for the day Friday after The Boston Globe reported that one of the suspects had worshipped there.

Related:

The quiet street where 5 days of terror ended

Lone officer confronted suspects on dark street, official says

'Best day of my life,' mom says after bomb victim opens eyes

What's next: The interrogation of the Boston bombing suspect

Secret weapon: How thermal imaging helped catch bomb suspect

Parents of suspects say their children were framed

Family of dead suspect's wife: 'Our hearts are sickened'

On social media, Tsarnaev's mixed religious fervor, whimsy

A nation cheers arrest of Boston bombing suspect

Slideshow: Timeline of terror hunt and capture

This story was originally published on Sat Apr 20, 2013 8:42 PM EDT

Courtesy of the Tripathi family

Sunil Tripathi and his mother, Judy Tripathi.

The family of missing Brown University student Sunil Tripathi, whose name was repeatedly blasted across social media as a suspect in the Boston Marathon bombing, said it has been emotionally staggered by the erroneous reports.

His sister, Sangeeta Tripathi, said the family was forced to temporarily freeze its "Help Us Find Sunil Tripathi" Facebook page after that site — beginning Thursday evening — was peppered with a flurry of harsh and untrue posts about the student, who has been missing without a trace since March 16. The family is eagerly awaiting official word from law enforcement clearing Tripathi.

NBC News, via correspondent Pete Williams, reported on Twitter shortly after 2 a.m. Friday: "Speculation that one of the bombing suspects is a missing student is not correct," citing law enforcement sources. 

"It seems this is just the ugly underbelly of viral social media," Sangeeta Tripathi said. "But a lot of stir can be created through just a complete accusatory and unsubstantiated effort." 

"It’s had a huge cost on our family. We are all very depleted right now, just baseline over the past 34 days, and this has been very, very difficult," she added. "Without Sunil in our life, it's been very hard to have that publicity. 

"We are absolutely convinced, with no question at all, it’s not Sunil. We are eagerly awaiting formal public news to calm the pain on my family. We have not received a public apology at all. The FBI is incredibly busy as you can imagine in the investigation. The second law enforcement releases complete information on the suspects, it’s going up on our Facebook page." 

Twitter was ablaze overnight with tweets from users who said they'd heard Sunil Tripathi's name mentioned on Boston police radio frequencies in connection to the bombing investigation and during the massive manhunt that quickly unfolded Thursday night. The Tripathi family said it has no information corroborating that Boston police mentioned Tripathi's name. 

'Intense and ugly comments'
On Twitter, ‏‪@YourAnonNews tweeted overnight: "Police on scanner identify the names of ‪#BostonMarathon suspects in gunfight, Suspect 1: Mike Mulugeta. Suspect 2: Sunil Tripathi." That was retweeted more than 3,000 times. On the twitter account for "Kevin Michael TV," which lists him as "behind the camera at WFSB news Channel 3 Eyewitness News" in Hartford, Conn., a similar tweet came at roughly the same time: "BPD scanner has identified the names : Suspect 1: Mike Mulugeta Suspect 2: Sunil Tripathi."

As with Tripathi, no one named Mulugeta has been named as a suspect by the police. 

Meanwhile, the social news and entertainment website Reddit became overnight, Sangeeta Tripathi said, "one of the more ugly and disgusting places that had a lot of traffic ... There were very intense and ugly comments throughout the last 12 hours. A moderator posted an acknowledgement that without formal evidence, accusations should stop."

On Friday afternoon, the Tripathi family received an email from Erik Martin, the general manager of Reddit, “to apologize personally and on behalf of all our employees for … some of the people on our site's role in the spreading of this false idea about Sunny.” The Tripathi family immediately forwarded that email to NBC News.

“It's an extreme situation and we are deeply sorry that your family got caught up in it,” Martin wrote in the email. “I can't imagine what it must be like for your family to deal with this on top of what you must already be going through.”

The Tripathi family's Facebook page, set up to help locate Sunil and, until Thursday, filled with messages of hope and pictures of the student, began being hit with posts Thursday evening "from individuals who for whatever reason were making the association between what happened (at the Boston Marathon) and him, Sangeeta Tripathi said. 

The Tripathi siblings — there are three, with Sangeeta being the oldest and Sunil the youngest — grew up outside Philadelphia, Sangeeta said. The family has been huddled in Providence, R.I., home of Brown University, since Sunil disappeared last month. His nickname is "Sunny." 

Asked if the viral nature of the misinformation was racially fueled, she responded: "I’m not going to comment on that."

The spread of false rumors online is nothing new, but the combination of confusion and breaking news can create a particularly toxic situation.

In the immediate aftermath of the Newtown, Conn., school shootings, when local officials incorrectly identified the shooter as Ryan Lanza, thousands of Twitter and Facebook users swarmed to repeat the accusations. Meanwhile, after the theater shooting in Aurora, Colo., Facebook users who shared the suspect's name, James Holmes, found dozens of false accusations left on the pages.

Related links:

• Suspects to carjack victim: We are the bombers
• Who are the brothers accused of the Boston Marathon bombing?
• An empty metropolis: Photos show deserted streets of Boston  
• What we know: Timeline of terror hunt
• ‘Dedicated officer’ gunned down by Boston Marathon suspects at MIT
• Slideshow: Bombings at Boston Marathon
• Boston bombing spurs Senate debate on tighter immigration screening
• Photos from Bostonians locked down amid terror hunt 
• Tweeting police chatter creates confusion over Boston suspect

Family photo via Facebook

JP and Paul Norden each lost a leg in Monday's bombings at the Boston Marathon.

Two brothers who went to the Boston Marathon to cheer on a friend each lost a leg in Monday’s bombing, their family said, asking the public for prayers.

Paul Norden, 31, and his brother, J.P., 33, were being treated at separate hospitals on Tuesday, their worried relatives rallying around them.

“J.P. is alert, knows what’s going on,” their mother, Liz Norden of Wakefield, Mass., told NBC News via text message from the hospital.

“[He] knows he lost his leg. He is in a great deal of pain,” she said, adding that he had a loud, incessant ringing in his ears from the blast.

The emotional wounds were just as bad, she said.

“He is a mess. He is very concerned for his brother Paul…burst into tears when he found out Paul lost his leg.”

J.P. had already undergone surgery, while Paul was back in the operating room on Tuesday afternoon.

“All I ask is to please, please pray for all of them,” the mother said.

Norden said Paul emerged from surgery late Tuesday afternoon. His mother said he is not able to talk yet but he squeezed her hand and tried to get up when she told him J.P. had survived.

"This is just overwhelming," she said.

On Monday, Liz Norden told the Boston Globe she was unloading groceries when she got a call on her cell phone from Paul, who was in an ambulance.

"Ma, I'm hurt real bad," he told her.

She soon learned the her elder son, who had been standing next to him, had also lost a limb.

“I am just so heartbroken,” she told NBC News as she shuttled between Beth Israel Deaconess and Brigham and Women’s Hospital. Paul’s girlfriend was being treated for burns at a third hospital.

The brothers, both roofers who had recently been laid off, were at the marathon to support their friend, firefighter Mike Jefferson, who escaped injury.

“I was a quarter-mile away from the finish line,” Jefferson told the Globe.

Three people were killed in Monday's twin bombings, which also injured at least 176 people. Authorities have not yet named a suspect in the attack.

Lee-Ann and Nick Yanni were standing about 10 feet from the finish line cheering on friends when the bombs went off. Shrapnel ripped through Lee-Ann's shin, causing her to need emergency surgery for an open fibular fracture; Nick sustained a pierced ear drum, NBC's Kerry Sanders reported.

Josh Reynolds / AP

Nicholas Yanni, 32, of Boston, speaks to reporters at Tufts Medical Center in Boston. He and his wife, Lee Ann Yanni, 31, were injured in the Boston Marathon bombing.

"It sounded like somebody had taken a cannon or some kind of bomb or something was right behind me," Lee-Ann told TODAY from her hospital bed.  "You could smell gunpowder and probably flesh at that point."

Lee-Ann was waiting for a skin graft Tuesday morning.

"People were on the ground. A lot of broken limbs – I think I saw a guy with no limbs at all," Nick told TODAY. 

Among those killed was 8-year-old Martin Richard of Dorchester, Mass., who was watching the race with his family, NBC affiliate WHDH reported. Martin's 6-year-old sister lost her leg in the blast; his mother suffered a serious brain injury and had surgery late Monday night, WHDH said.

"The kids were all up on the barrier," said Rep. Stephen Lynch, D-Mass., who told MSNBC's "Morning Joe" that he spoke to Martin's father, William, after the bombings. "They had their feet up on the pegs, trying to get a higher view. ... So they were all focused forward and the blast came from the back and the side."

The family also has a son in the fifth grade who was not injured, according to WHDH. 

William Martin, the father, is a runner but was not running in yesterday's marathon and was not injured, Lynch told MSNBC. The family was there to support friends who were in the race.

Slideshow: Boston Marathon explosions

Charles Krupa / AP

See images from the scene of the explosions.

Launch slideshow

Related:

Witness who ran toward marathon bomb 'saw bodies flying'

Amid the chaos and carnage in Boston, heroes emerge

'You're not in it alone': Good Samaritans take in marathoners

Timeline of a tragedy: What happened when

Marathoner: 'I just have to get over the finish line'

This story was originally published on Tue Apr 16, 2013 7:25 PM EDT

The first task for investigators in the bombing that rocked Boston on Monday will be determining whether the carnage was the work of an individual or a terrorist organization, experts said.

The scope of the attack at the high-security Boston Marathon doesn’t rule out a lone wolf, said Evan Kohlmann, NBC News’ terrorism analyst.

“There have been individuals who have been capable of doing something like this,” Kohlmann said, pointing to the 1996 Olympics bombing by anti-abortion radical Eric Rudolph.

But Kohlmann said an organized group – domestic or international – could also be the culprit.

“It could be half a dozen different causes, or just a crazy guy,” he said.

NBC News National Security analyst Mike Leiter agreed that even though it was a “pretty sophisticated attack,” the field of suspects is wide open.

“I wouldn’t go down any particular path,” Leiter said on MSNBC.

William Bratton, the former police commissioner of Boston, Los Angeles and New York, said it's important investigators approach the case with an open mind.

"You start with the assumption that you know nothing," he said.

They also need to be on the alert for false claims of responsibility that "will come out of the woodwork," Bratton said.

Kohlmann said forensics from the scene could give investigators important information. If the explosive used was military-grade, that would suggest foreign terrorists, and not someone closer to home jury copying bomb-recipes off the Internet, is responsible.

The most crucial clues, though, will come from closed-circuit camera footage from the area that could show the bomber planting the devices or fleeing the scene, he said.

He noted that in the 2005 London subway bombings, police used the cameras to quickly zero in on the suspects.

“My suspicion is this is something that they will be able to make significant progress on in a very short period of time,” Kohlmann said.

“The record of people who have gotten away with things like this is not very good.”