The cause of the deadly explosions at a Texas fertilizer plant last month remains undetermined, state and federal officials said Thursday.

Robert Champion, the agent in charge of the Dallas office of the Bureau of Alcohol, Tobacco, Firearms and Explosives, said at a briefing that investigators hadn't been able to rule out the possibility that the two blasts at West Fertilizer Co. were caused by an intentionally set fire.

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The briefing was delayed a half-hour so authorities could talk to the families of the victims, said state Fire Marshal Chris Connealy, who promised to "leave no stone unturned to make sure everything is done."

"This community has suffered a great tragedy," he said, adding that 30 different local, state and federal agencies were working "with one common goal: to understand what happened so we can give closure to these families."

The explosions in the town of West, near Waco — which killed 15 people and injured hundreds of others on the night of April 17 — devastated a 37-square-block area, creating a crater 93 feet wide and 10 feet deep, Champion said.

Twelve of the dead were firefighters and other first responders, and Champion paid special tribute to them.

"They were doing their job and showing their bravery when they were fighting that fire," he said.

Investigators said the fire began in a fertilizer and seed building called the seed room. They said the possible causes included arson, a failure of one of the plant's two electrical systems and a compromised battery on a golf cart.

The golf cart had been recalled from the manufacturer, said Brian Hoback, a national response team investigator for the ATF, who said "there's a history of golf carts' actually starting fires" when their batteries fail. He said the cart couldn't yet be ruled out because it hadn't been fully recovered from the scene.

Many other triggers had been speculated upon as the cause, including the weather, some sort of spontaneous ignition, failure of the facility's second electrical system, two ammonium compounds used in the fertilizer-making process and smoking. Investigators said all of those had been ruled out.

And they chillingly said the explosions could have been much worse.

The fire caused at least 28 tons of ammonium nitrate, a highly combustible powder, to explode in the seed room, they said. Sitting outside was a rail car holding about 100 more tons of the compound — which fortunately didn't blow up.

Because the inquiry is being handled as a criminal matter, Champion and other investigators refused to go into other details of their investigation, which they said was expected to take several more months.

West Fertilizer said in a statement that it would have no comment other than that "the authorities repeatedly emphasized that their investigation continues, as does ours."

Champion, meanwhile, wouldn't comment on the arrest of Bryce Reed, a paramedic who helped the victims, who pleaded not guilty Wednesday to a count of unlawfully possessing an unregistered destructive device.

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This story was originally published on Thu May 16, 2013 6:59 PM EDT

Bureau of Alcohol Tobacco and Firearms and Explosives investigators have so far found no evidence that a bomb caused last month's deadly explosion at a West, Texas, fertilizer plant, law enforcement officials told NBC News on Wednesday.

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The news comes ahead of a Thursday press conference at the site in which officials from the ATF will discuss their work to investigate the cause of the disaster and lay out their initial findings.

Officials from the Texas fire marshal’s office are also expected speak on the explosion that killed 15 people and injured hundreds while leveling much of the tiny town, NBC Dallas-Fort Worth reported.

It was not revealed, however, what precisely officials will say about the cause of the blast.

And one official told NBC News that he did not expect mention of a first responder who is charged with owning pipe bomb components.

Last week, the Texas Rangers and McLennan County Sheriff's Department opened a criminal investigation into the blast on the same day the paramedic, Bryce Reed, was arrested.

Officials, however, have not made any connection between Reed and the opening of the criminal investigation.

On Wednesday, Reed pleaded not guilty to one count of unlawfully possessing an unregistered destructive device.

Related:

Texas plant explosion investigation results to be released Thursday

Satellite images show West, Texas before and after fertilizer plant explosion

The brothers accused in the Boston Marathon bombings originally planned to set off explosives on July 4 — but changed their minds and decided on Patriot’s Day, officials with knowledge of suspect Dzhokhar Tsarnaev’s interrogation told NBC News.

Investigators also now have a good idea of how and where the pressure-cooker bombs used in the attack were constructed. But they still are trying to determine where the components in the explosives came from.

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Officials say Tamerlan Tsarnaev, 26, and his brother Dzhokhar Tsarnaev, 19, dropped pressure-cooker bombs stashed in backpacks in crowds watching runners at the finish line of the marathon on April 15.

Dzhokhar allegedly told his interrogators the weekend after he was arrested that he and his brother originally intended to set off their bombs somewhere on the Fourth of July, officials said.

But, according to the officials, Dzhokhar said that when the brothers finished the bombs sooner than they expected, they decided to stage the attack earlier, on Patriot's Day, a proud holiday in Boston that hosts the marathon, a Red Sox game and other festivities.

Officials say the surviving suspect also said the bombs were built in the house of his brother, Tamerlan. Authorities had previously disclosed that explosive residue had been found there.

And a backpack that officials say was snatched from Dzhokhar Tsarnaev’s dorm room then thrown away by three of his friends before being recovered is providing some clues on the bombs.

Federal agents recovered the backpack in the New Bedford, Mass., landfill. It contained fireworks tubes that had been emptied of their powder.

According to the FBI, the found fireworks were from a store other than the Phantom Fireworks shop in Seabrook, N.H., which disclosed a purchase by Tamerlan Tsarnaev in February.

The FBI was checking on sales with other dealers in the area.

In addition, the FBI said the backpack contained a jar of Vaseline petroleum jelly.

"Bombers use Vaseline as a binder and thickening agent,” an FBI investigator said. “They mix it with explosive powder in hopes of making the mixture a little more reliable."

The use of Vaseline is not mentioned in the al Qaeda online magazine that investigators believe the brothers used as a blueprint to make their bombs, but it is widely discussed elsewhere on the Internet.

Authorities say the three friends — who have been hit with obstruction of justice and lying charges — also took Dzhokhar Tsarnaev's laptop computer from his dorm room but did not throw it away and have since given it to the FBI.

Meanwhile the body of Tamerlan Tsarnaev was moved to a funeral home on Thursday evening at the request of family members, according to the Massachusetts Medical Examiner’s Office.

Soon after receiving the body, the funeral home must file a death certificate, which would make public Tsarnaev’s cause of death.

Tamerlan Tsarnaev was killed in a firefight with police in the early morning hours of April 19 in the Boston suburb of Watertown. His precise cause of death, however, has remained unknown, since a death certificate or autopsy results have not been made public.

The name of the family members who requested the release of the body and the funeral home were not released.

Dzhokhar Tsarnaev is in a prison hospital awaiting trial on terrorism charges.

He has told investigators the brothers acted alone in concocting the deadly plot, and planted the bombs to defend Islam after the U.S.-led wars in Iraq and Afghanistan, law enforcement officials told NBC News.

Related:

Who's who in the Boston Marathon bombing investigation

This story was originally published on Thu May 2, 2013 7:13 PM EDT

As the military wrestles with an alarming number of sexual assaults — an issue former Defense Secretary Leon Panetta called "an affront to the basic American values we defend" — the Department of Defense has adopted a novel technique that fundamentally changes the way investigations are handled.

Hundreds of investigators and prosecutors across all military branches have participated in a special victims unit course at Fort Leonard Wood in Missouri that focuses on a unique forensic interviewing technique designed to elicit detailed descriptions of an attack. 

With traditional methods, this “psychophysiological” evidence has previously been difficult to obtain from both the victim and suspect, but can often break open an otherwise difficult case in which there is little or no physical evidence.

The technique was developed by Russell W. Strand, a former special agent with the Army’s Criminal Investigation Division and current chief in the education and training division at the Army’s Military Police School. Strand began evaluating sexual assault training in 2004 as numerous reports of rape in combat zones and at home became public.

He soon discovered that law enforcement, both military and civilian, expected victims to recount their trauma blow by blow, with precise details that could convince any skeptical jury or judge.

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That may seem like conventional wisdom, but Strand frequently found victims rarely had such clarity. He consulted experts, immersed himself in neurobiological research, and found that the expectation doesn’t align with the science of trauma and memory.

In the midst of an assault, the brain does not capture every moment of trauma as if it were recording a film. The pre-frontal cortex can "shut down" or become severely impaired. As a result, many victims can’t provide a contextual or linear account of the event, but fragmentary memories, perhaps the tone of the suspect's voice or, when a sense of defeat has set in, a recollection of the way a lamp looked as she or he was being assaulted. In interviews with investigators, Strand said, the lack of a victim’s ability to recall specifics quickly sowed doubt.

“We started looking at that (research) and started looking at what kind of evidence we gather in a sexual assault,” Strand said. “We weren’t collecting the right data.”

Start with memories, not at the beginning
Strand’s technique, which he has termed the forensic experiential trauma interview (FETI), begins with an investigator expressing empathy toward the victim in order to establish trust. What comes next is not a set of rapid-fire questions about the assault. Strand believes that approach, long used by law enforcement, pressures and confuses the victim. Instead, investigators are trained to simply ask what the victim is able to remember about the experience.

Asking the victim to “start at the beginning” — another hallmark of traditional police work  — forces the victim to try to retrieve memories that may not have been encoded in the first place, which can lead to inaccurate or distorted recollections. Some victims may then doubt the memories they do have while investigators wonder if he or she is making up the assault. 

What’s more important, according to Strand, is eliciting the victim’s sensory memories, which helps to create a three-dimensional picture of the attack. It also allows the victim to relate the experience in a way that makes sense and yields vital information that can be presented to a jury.

Dr. Jim Hopper, a clinical instructor of psychology at Harvard Medical School, says Strand is teaching good clinical skills for interviewing traumatized people, adapted for an investigative context. Hopper is a guest lecturer for the course, and teaches the effects of sexual assault on the brain.

Lori Jones, a civilian special agent stationed at Fort Leonard Wood, said that once she was trained in the interviewing technique, she was able to collect much better evidence. If a victim describes feeling “frozen” during an attack, for example, Jones is able to understand that as tonic immobility, a physiological response to terror or trauma that often leaves a person numb, starring in a fixed or unfocused manner and unable to move or cry out.

The interview technique can also lead to unwitting admissions of guilt by attackers. When asked to describe a victim's behavior, suspects and victims have recounted the same details, Jones said.

“One of the biggest blessings in FETI has been being able to take forward an investigation with no tangible evidence,” said Jones. “I have the ability to take this to my supervisor and say, ‘This is what the victim is articulating, these were the things she felt her body doing ... and he saw her doing what she was doing.’”

This critical information has helped Jones educate commanders and prosecutors who falsely assume that a victim’s lack of resistance or inability to immediately call the police, for example, is evidence of lying.

Joanne Archambault, a former investigator and executive director of the nonprofit training, education and policy organization End Violence Against Women International (EVAWI), said that evidence gathered by techniques like FETI are essential in conducting a thorough investigation. The interview is a "big piece of the puzzle" that helps an agent corroborate a victim's account.

"Victims are much more likely to talk to us when they’re being given an opportunity to provide a narrative in their own terms," Archambault said. "You can’t get to prosecution and conviction without that."

'Visionary' technique
There are other investigation techniques that attempt to obtain sensory details from victims, but integrating scientific research on how a victim's brain responds to trauma is a unique element that has won Strand accolades. Last year, EVAWI gave Strand its Visionary Award.

Archambault, who investigated or supervised 10,000 sexual assault cases at the San Diego Police Department before retiring in 2002, said that law enforcement often has little or no training in interviewing victims of traumatic crimes. As a result, the experience can feel like an interrogation. She has observed a FETI training class, which Strand also teaches to civilian police departments, and says the focus on about trauma and its effect on memory is novel. 

“In a nutshell,” she said, “he’s been dedicated to making improvements in a culture.”

The struggle to understand and address sexual assaults in the military has been very public. Last week, members of the Senate Armed Services Committee excoriated military leaders for permitting an environment that enables sexual assault.

In 2011, 3,192 sexual assault reports were filed, but the Department of Defense says the number is closer to 19,000 based on anonymous surveys of active-duty service members conducted in 2010. Of the 3,192 reports, only cases on 1,518 subjects were brought forward for disciplinary review. 

The Army tracks the number of cases brought forward by prosecutors; anecdotally, Jones said it appears FETI has helped increase this number, but the Army's Criminal Investigation Command did not have those statistics readily available. Those familiar with the technique are hopeful that it is changing pervasive attitudes and assumptions about victim behavior.

In a statement to NBC News, Rep. Niki Tsongas, D-Mass., who chairs a caucus on military sexual assault, called FETI a “step toward more successful investigations and prosecutions.”

The Department of Defense has incorporated the course as part of its multi-pronged approach to prevent sexual assault in the military. "When one does occur, effective processes and trained professionals must be in place to support victims and ensure delivery of justice," Cynthia O. Smith, a spokeswoman for the DoD, told NBC News.

Since 2009, 721 special agents and prosecutors from every branch of the military have attended the training. Another 315 are scheduled to complete the course by the end of this September, and DoD has funded more than 400 seats at the course through fiscal year 2017.

Strand says he and his team encountered some early resistance from investigators accustomed to the traditional interviewing technique, but that dissent has since ebbed.

“We’re over the (point) where more people get it than don’t,” he said. 

Rebecca Ruiz is a reporter based in the Bay Area.

Related:

• Senate panel members suggest overhaul of military justice system 
• Accuser in Air Force sexual assault case 'frustrated' at overturned verdict
• Civil Rights Commission urged to order audit of military sex-assault cases
• Reported sex assaults leap 23 percent at US military academies
• Sex-assault victims in military say brass often ignore pleas for justice

The psychiatry staff at Madigan Army Medical Center was not encouraged to overturn diagnoses of post-traumatic stress disorder to save the government money, according to investigation documents provided to NBC News.

The Army previously said it found no evidence of wrongdoing at the Tacoma, Wash., hospital, but had not released the investigation documents until Friday. As recently as last month, the Army said it would not share the findings and denied Freedom of Information Act requests by local media.

The investigation, conducted last spring, sought to determine whether or not the commander of Madigan, Col. Dallas Homas, exerted any “undue influence” on PTSD diagnoses. Homas was reinstated last July and the investigation documents contain numerous glowing reviews of his leadership and no indication that he pressed the staff to consider the cost of diagnosing a soldier with PTSD.

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That claim stemmed from a 30-minute presentation given in September 2011 by the hospital’s chief of forensic psychiatry, in which he noted that a PTSD diagnosis could cost the government over $1.5 million in disability payments over a soldier’s lifetime.

The 100-page investigation document contains several interviews with Madigan staff members who say the comment was made in less than a minute and taken out of context.

When questioned about the remark, the commander explained that forensic psychiatrists must take into consideration all factors “that could bear on an individual’s diagnosis,” including financial gain, the document showed.

“... It is clearly being blown out of proportion and used to attack [redacted] and his team,” Homas said. “I have not seen any evidence that concern over saving government money is a driver of arriving or not arriving at a diagnosis.”

In the fall of 2011, some soldiers had complained that their PTSD diagnoses had been switched to conditions like anxiety disorder, which could have affected their medical retirement rating and the amount of their disability payments.

Homas pointed out during the investigation that while 14 soldiers were not diagnosed with PTSD, at least 44 soldiers who entered the medical retirement process were ultimately given that diagnosis.

“If this were about saving money, this section has failed has failed miserably,” he said.

The investigation interviews also revealed that some staff faced tense situations when giving a diagnosis.

“Sometimes some soldiers can get so upset that they might act out in some manner, perhaps expressing threats," the chief of behavioral health said to the investigator. "The easy thing to do is just give the patient what they want. The (forensic psychiatry) clinicians work very hard to do what is right.”

Homas said in his interview that some soldiers made death threats against forensic psychiatrists.

The investigating officer wrote that only two individuals, who were ombudsmen, made “unsubstantiated allegations” regarding the forensic psychiatric process. Both were suspicious of changes to soldiers’ PTSD diagnoses, but did not believe Homas advised staff to consider the cost as a factor.

The investigating officer agreed with Madigan staff that the ombudsmen had misunderstood the context of the Sept. 2011 comment.

One ombudsman said soldiers whose diagnoses were reviewed by the forensic psychiatric team were very distressed upon being told they did not have PTSD. In some cases, medical professionals previously told them they had the disorder.

That ombudsman said their lives had been “turned upside down” as a result, and that some evaluations contained language insinuating that the solders were liars and malingerers.

Though the forensic psychiatry team was essentially absolved by the report, the Army has stopped the practice of using such teams to vet PTSD diagnoses; Madigan was the only Army hospital to do so.

“The fact that the Army had to bring in new doctors to reinstate hundreds of PTSD diagnoses for local servicemembers and that they have implemented major behavioral health policy changes nationwide in the wake of the Madigan cases are clear evidence that problems existed on base in properly identifying the invisible wounds of war,” Sen. Patty Murray, D-Wash., said in a statement to NBC News. Murray pushed for the investigation into the PTSD diagnoses at Madigan.

As part of the investigation, a review of 431 Madigan cases — some of which had been overturned — led to PTSD diagnoses for 150 soldiers by last October. The Army recently said that Madigan’s variance rate for diagnoses was not outside the norm. 

Rebecca Ruiz is a reporter based in the Bay Area.

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• Soldier Hard's hip-hop lyrics reveal PTSD's rough edges
• Hundreds of thousands of veteran spur free benefits

 

The Justice Department announced Thursday that it has ended a lengthy investigation into the CIA's interrogation and treatment of prisoners without bringing any criminal charges. 

U.S. Attorney General Eric Holder announced the investigation into the deaths of two suspected terrorists  who died in CIA custody -- one in Iraq and another in Afghanistan -- was ended without charges because "the admissible evidence would not be sufficient to obtain and sustain a conviction beyond a reasonable doubt." 

The two cases include the highly publicized case of Manadel al-Jamadi, who died in a shower stall at the infamous Abu Ghraib prison in Iraq while in CIA custody.  Several U.S. soldiers, who were photographed with al-Jamadi's body, packed in ice inside a body bag, were later prosecuted and convicted in military courts for prisoner abuse. 

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The investigation spanned more than four years. It began with an investigation into the CIA's destruction of videotapes of aggressive interrogations of terrorist suspects, but was later expanded to include the deaths of the two detainees. 

In all the Justice Department investigated the treatment of 101 detainees who been held in U.S. custody since 9/11. 

CIA Director David Petraeus issued a statement thanking everyone at the CIA who supported the Justice Departments investigations.  

In an apparent effort to put the incidents and investigations to rest, Petraeus added, "As intelligence officers our inclination of course is to look ahead to the challenges of the future rather than backwards at those of the past."

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An investigation of the FBI's handling of the events leading up to the shootings at Fort Hood, Texas, in November 2009, concludes that agents made a series of mistakes, failing to follow up on important questions and to share information widely enough.

"We do not find, and we do not suggest, that these mistakes resulted from intentional misconduct or the disregard of duties," concluded William Webster, the FBI's former director who led the investigation. "Indeed, we find that each special agent, intelligence analyst, and task force officer who handled the information acted with good intent."

Click here to read the full report (pdf)

Most of the shortcomings have been previously disclosed, and some resulted from a lack of training and of understanding military nomenclature. For example, agents in San Diego, who were investigating al-Qaida propagandist Anwar al-Awlaki, noticed on December 17, 2008, that Nidal Hasan, who would become the Fort Hood shooter, sent al-Awlaki an e-mail asking about soldiers who kill fellow military personnel with the aim of "helping muslims fighting jihad."

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Related: Judge delays Fort Hood shooting hearing over Hasan's beard

The San Diego agents decided against sending out a broadly disseminated message that would have alerted the system that a member of the US military was communicating with a known al-Qaida terrorist. The agents noticed that a summary of his military records said Hasan was a "Comm Officer," and they assumed it meant he was a communications officer and might have access to the system that would contain such an alert message. In fact, the abbreviation meant Hasan was a commissioned officer.

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The report also says agents in the FBI's Washington field office failed to follow through more aggressively to the leads developed in San Diego. Part of the problem, the report said, was that the FBI received only glowing accounts from the Department of Defense about Hasan's career. Agents were never told that he was actually considered a poor performer who was often on probation.

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Investigators are probing whether contamination at a city laboratory could have led to the match between DNA found at the murder scene of a Juilliard student eight years ago and a chain used at a recent Occupy Wall Street protest, law enforcement sources said Wednesday.

Two sources said investigators are looking at an NYPD lab technician and whether that technician came in contact with both pieces of evidence, causing the match, NBCNewYork.com reported.

Earlier in the day, a spokeswoman for the medical examiner's office said all employees there were screened as possible source of the DNA and that all of the medical examiner's employees were ruled out as the source of possible contamination.

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Further testing to try to finalize the source of the DNA is continuing, the medical examiner's spokeswoman said.

Read the original story at NBCNewYork.com

"We are still actively investigating the DNA match," said the spokeswoman, Ellen Borakove.

NBC 4 New York reported Tuesday that DNA evidence from the scene of Sarah Fox's murder in Inwood Hill Park in 2004 has been connected to DNA from a chain left at the Carroll Street F station in Brooklyn during a protest at 7:05 a.m. on March 28.

Police Commissioner Ray Kelly said Wednesday that he could not comment on the case.

Fox was found nude and strangled in the park in May 2004, days after she disappeared during a daytime jog. Investigators recovered her pink CD player in the woods just yards from her body.

Dimitry Sheinman, 47, has long been considered a suspect in the Fox murder. He was never charged in the case and has been living in South Africa.

Sheinman recently returned to New York City, proclaiming to be a clairvoyant with knowledge of the killer's identity. He asked to meet with police to give them information about the alleged killer; the details he offered are unknown.

Sources said Sheinman remains a leading person of interest. His DNA, which police have on file, was not found on the chain or at the 2004 murder scene. The DNA of the crime-scene detective who handled the chain has also been ruled out, sources said.

Sheinman did not respond to a request for comment.

In March, protesters chained open emergency gates and taped up turnstiles in eight subway stations and posted fliers encouraging passengers to enter for free.

"I hope the person or persons who killed this young woman are found and brought to justice," said Bill Dobbs, a spokesman for Occupy Wall Street. "We don't know anything about it ... I hope no one jumps to any conclusions."

No one was arrested in the March subway protest incidents.

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Ever wonder what it's like to have FBI agents knock on your door? Or to have them walk into your business unannounced and walk away with your computer?  Jamie McClelland and Alfredo Lopez can tell you.

Their recent run-in with the men in black – the result of a spate of email bomb threats to the University of Pittsburgh -- offers a rare glimpse into the collision between free speech rights and the benefits of anonymity on one side with the needs of law enforcement to act quickly in the face of real threats on the other.

Their tale ends with an odd twist: FBI agents, caught on video, returning the server only four days after it was seized from a co-location facility in New York City. At the moment, no one knows why the FBI would take that unusual step. FBI Special Agent Bill Crowley said the agency wouldn't comment on either the seizure or the return of the server.

Federal investigators and local officials in Pittsburgh were scrambling last month as bomb threats targeting the University of Pittsburgh piled up. Within days, 46 such threats were logged, causing massive disruption as students and teachers were continually evacuated from building after building.  Parents and school officials pressured law enforcement to solve the case. For some reason, the FBI thought a server in a small facility in New York City might contain a crucial clue.

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McClelland and Lopez run a progressive Internet organization called MayFirst/PeopleLink, which helps democracy-seeking groups around the world use the Web to organize. Together with sister organization RiseUp, MayFirst/PeopleLink offers email services, mailing list support and other Web tools. But their services make a promise that's critical to people fighting oppressive regimes: All data is encrypted, guaranteeing total anonymity to those who need it.

 

 

 

McClelland was on a conference call in MayFirst/PeopleLink's Brooklyn office -- which is in the same building where Lopez and his wife live -- on April 11 when he saw two men in suits standing at the door.

"I thought they were Jehovah’s Witnesses, but I joked with people on the call that it was the FBI," he said.  Moments later, it was no joke.

The agents flashed their badges and asked if they could come in; McClelland refused.  They asked if they could step into the vestibule. He refused again.

"I had had some rudimentary training,” he said. “It certainly had occurred to us that we might some day get a visit from the FBI given the nature of what we do. But this wasn't what I expected. I was surprised at how easy it was to say ‘no’ to them...There was no intimidation, none of that. The agent appeared more nervous than me, and I was pretty nervous."

Standing outside, the agents then showed printouts of a few emails with full headers to him, saying they were related to the Pittsburgh bomb threats. At that point, McClelland hadn’t  heard about the threats, so he said he didn't know anything about them. They asked if he knew anything about ECN.org, a server which appeared in the e-mail headers. Again, he said “no,” truthfully.

"I asked if I could have copies of the emails. The agents said “no.” But I then asked if I could get pen and paper and write down details of what we were looking at. They let me do that," McClelland said. "I then asked them if they thought our server was compromised. But they couldn’t tell me anything. So I asked for their business card and told them we would research it."

The agents left, but McClelland’s day had only just begun. What was ECN.org? Why did the agents show up unannounced? And most important, what would happen next? He was sure that wasn't the end of it.

"When you are visited by the FBI, even when it goes relatively easy like it did, your entire life gets put on hold as you deal with all the implications," he said. McClelland called Lopez and other leadership team members, and then called the Electronic Frontier Foundation for legal help.

“There were three hours of calls to run through things and make sure we had everything covered," he said.

Initially, Lopez and McClelland assumed that one of their members had been hacked, and the account used for illegal purposes. Simply patching whatever security hole existed could end the problem. But a visit to ECN.org indicated there was a much more complex issue.

ECN stands for the European Counter Network, an independent Internet service provider in Europe. It shares much the same mission as MayFirst/PeopleLink. On ECN.org, the provider offers anonymous email services through a service called "Mixmaster." Using Mixmaster, email users can achieve nearly undefeatable anonymity -- multiple servers pass messages from one to the other, each time stripping out header information and replacing it with false data, making it nearly impossible for investigators to "trace" the message to the original sender. 

ECN had subcontracted space on RiseUp's New York City server; RiseUp had in turn subcontracted that space from MayFirst/PeopleLink.  It now appeared that the FBI believed someone connected to the Pittsburgh bomb threats had used ECN's anonymous email capabilities, which led to FBI agents knocking on the door at Alfredo Lopez's home office.

"If you had asked me before this happened if one of our members ran an anonymous remailer, I would have said, 'probably,' " said McClelland. "That's exactly the kind of thing we want to support and we want to protect."

When correctly configured, anonymous remailers leave no trace at all. There are no log files to check, no other server "fingerprints." After making sure the server was running properly, McClelland called the FBI agent on the business card and told him all he knew about ECN, which essentially was nothing.

"We told him we suspected there was an anonymous remailer, there's nothing else we can tell you," he said. "We decided that was our best strategy ... to minimize disruption to our members. We didn't want to risk going to the next level of escalation."

The strategy failed.  The next day, MayFirst/People Link received a subpoena demanding that the organization answer a series of questions about its server. With help from the EFF lawyer, they sent the responses on Monday, April 16.

"At that point, we thought everything was OK, that we were done, and ready to move on," he said. 

Then on Wednesday, April 18, at around 6 p.m., things took a turn for the worse.

"I got a call from a tech who said, 'Jamie, the server isn't responding.' So he went to look for it in the rack and found that it was gone," McClelland said.

Later, Lopez and McClelland would learn that the FBI had produced a search warrant when it showed up at the XO Communications Manhattan server farm, where the MayFirst/PeopleLink server was housed, which gave agents the right to take the box. But at the time, they could only guess what happened.

"We filled out a help ticket that said, 'Our server is missing.'  We've never done that before," McClelland said.  "I can't emphasize enough that we received no communication from the FBI. From a human point of view, that is atrocious. But from a legal point of view, they don't have to do any more."

The impact was immediate, and devastating, for both MayFirst/PeopleLink and RiseUp. Hundreds of mailing lists, websites and email accounts were immediately knocked offline.

“The FBI is using a sledgehammer approach, shutting down service to hundreds of users due to the actions of one anonymous person,” Devin Theriot-Orr, a spokesperson for RiseUp, said  in a statement at the time. “This is particularly misguided because there is unlikely to be any information on the server regarding the source of the threatening emails.”

While Lopez was scrambling to find a way to get the organizations back online, a camera with motion detection capabilities was installed at the server facility by an assistant.

"We thought it was a little like shutting the barn door after the horse ran out, but we did it anyway," he said McClelland said.

Generally, when FBI agents seize computers as part of an investigation, they're not returned for months, or even years. But within a week, a worker in the server room noticed that the motion detector camera had been activated on April 23. When he looked at the video, the tale took an even more unusual turn.

The video shows two men in suits -- apparently FBI agents -- placing the server back in its rack.  But the box isn't merely dropped off. The two appear to be plugging it in, and then watching the machine for a few minutes, perhaps looking to see if it is operating correctly.

Why would they do that? The FBI refused to answer a question about that.

But Lopez has a theory. There's only one way to defeat most anonymous email services: to compromise the computer that processes the emails with special software -- a virus -- that could defeat the anonymizing software.

"There was not even a scintilla of expectation that this server would return to our rack. It's the most amazing thing," Lopez said. "It's possible they put device on it or a virus or Trojan of some kind." 

MayFirst/PeopleLink later posted the FBI agent video online. The agency hasn't commented on it.

The server has not been returned to service; the organization is currently auditing the machine to see if it has been tampered with.

"I can tell you that's the burning question in my mind. We are planning on doing a full diagnostic on server to see if we detect anything on server," McClelland said. 

But even if it hasn't been tampered with, Lopez said he's outraged that U.S. federal agents would compromise Internet access for global groups fighting for democratic rights while hunting for evidence that doesn’t exist.

"Look at the atrocity of them going in and taking a computer ... and disrupting all this information, and potentially getting all this information from hundreds of people not even accused of a crime," Lopez said. "This is serious … for people all over the world who depend on this stuff for their day to day work. To have it taken away by some other government, it's really unfair to them in every conceivable way."

The MixMaster service was uninterrupted by the server seizure; anonymous messages were simply routed through other servers.

MayFirst/PeopleLink and RiseUp both told their members that no identities were compromised during the FBI seizure -- all data on the server is encrypted and there's no reason to believe the encryption was compromised. Still, U.S. government action against anonymous Web services could have a dangerous chilling effect, fretted Lopez.

"In some parts of the world, privacy and anonymity are a matter of life or death," he said. "These services are used for important work, and in many countries, they are the only way to communicate without putting yourself in serious danger."

The Electronic Frontier Foundation issued a statement last week accusing the FBI of "overreaching."

"The fact that the FBI's investigation led them to an anonymous remailer should have been the end of the story. It should have been obvious that digging deeper wouldn't lead to helpful information because anonymous remailers don't always leave paper trails," wrote Hanni Fakhoury. "So enough is enough. The government's ability to search a person and their property -- and in this case, shut down speech -- is an extraordinary power that can easily be abused. Law enforcement needs to do its research before resorting to an extremely intrusive search warrant that intrudes on innocent people's privacy, causes significant disruption to harmless activity, and silences speech. And as we've argued before, search warrants for electronic devices shouldn't be limitless."  

Lopez, who has two children in their 30s, said he understands why parents in Pittsburgh were concerned for their children's safety during the repeated bomb scares.  But he warned that repression often begins with "people who mean well."

"These people making the threats, these are jerks, nobody wants to protect them," he said. "But what do you give up when you give up freedom in exchange for the illusory feeling of security?  You can't trample people's rights because when you do, the terrorists have won."

The Pittsburgh bomb threats stopped on April 21. No bombs were found. There have been arrests in connection with the incidents, but authorities are still investigating.

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