BOSTON — Investigators were zeroing in Wednesday on video footage from a department store security camera, possibly showing a man wearing a large backpack and then dropping it, in the first sign of a possible breakthrough in the investigation of the Boston Marathon bombings.
A Boston city official told The Washington Post that the Lord & Taylor camera on Boylston Street, directly across from the site of the blasts, is of “special interest” to investigators. CNN reported that authorities have used the footage and other footage to identify a possible suspect.
The Boston Globe said authorities are reviewing an image of a potential suspect “carrying, and perhaps dropping, a black bag” at the bombing scene. A photo circulated on the Internet site Reddit appeared to show a man wearing a backpack at the site and then walking away without it.
Those reports have not been independently confirmed, and the FBI and Boston police said no arrests have been made, despite other media reports that said a suspect was in custody. And some previous investigations of terrorist incidents yielded suspects who turned out not to be involved.
Massachusetts Gov. Deval L. Patrick (D), speaking on CNN, cautioned that while the investigation is “making some progress,’’ it is likely to unfold slowly. “It’s going to be methodical…this is going to take some time, a lot of time,’’ said Patrick, who has been briefed by investigators and asked the public for “patience.’’
If authorities do indeed have a suspect, it would be a major development in the massive probe of the bombings, in which explosive devices crafted from pressure cookers and stuffed with nails and ball bearings killed three people and injured at least 176.
With no one claiming responsibility for Monday’s attack, hundreds of investigators in Boston and Washington are combing through more than 2,000 video and still images of the race route, searching for clues that might help determine whether the bombings were an act of domestic or foreign terrorism, planned by an organized enemy or a lone actor.
“The range of suspects and motives remains wide open,” FBI Special Agent in Charge Richard DesLauriers said at an evening news conference in Boston. He said that the investigation is “in its infancy” and that evidence — including fragments of BBs and nails, as well as pieces of black nylon that could have been part of an “unusually heavy” backpack or bag holding the bombs — has been sent to the FBI lab at Quantico, where technicians will try to reconstruct the devices. He said it is not known how many people set off the bombs.
“It’s our intention to go through every frame of every video,” Boston Police Commissioner Ed Davis said.
(See the latest updates on the Boston Marathon bombings here.)
In the first successful U.S. terrorist attack of the smartphone era, that means authorities face the daunting task of looking at thousands of images from phones, business- and government-owned surveillance cameras, and even runners’ head cameras.
Authorities urged that anyone with images of the area call 800-CALL-FBI (800-225-5324).
“We are particularly interested in reviewing video footage captured by bystanders with cellphones or personal cameras near either of the blasts,” said Attorney General Eric H. Holder Jr. “In an investigation of this nature, no detail is too small.”
The danger in any such investigation is that officials will be so overwhelmed by raw data that important clues may be missed. Philip Mudd, a former senior official at the FBI and the CIA, said that “99.4 percent of what you have is chaff. The wheat will emerge, but it could take a few days unless you get a break.”
Federal investigators are scrubbing every fragment from the bombs for clues about where its components were obtained and by whom.
President Obama, who plans to travel to Boston on Thursday for an interfaith service dedicated to the bomb victims, called the attack “heinous and cowardly” and termed it “an act of terrorism.”
Secretary of State John F. Kerry, a Bostonian who represented Massachusetts for decades in the U.S. Senate, spoke emotionally about the impact of the bombing Wednesday morning, while making his first appearance before Congress in his new job.
The granddaughter of one of his strongest political supporters in Massachusetts was injured in the blasts and is “fighting to keep her legs,” Kerry said. “We’re not going to be intimidated by this,” he added, his voice breaking. “We’re going to find out who did this.”
Police said they do not have any suspects. After a briefing by intelligence officials, Sen. Saxby Chambliss (R-Ga.) said, “There are a lot of things that are surrounding this that build an indication that it may have been a domestic terrorist.” But neither he nor law enforcement officials cited any specific evidence pointing to a source of the attack.