BOSTON -- No one has been arrested in connection with the Boston Marathon bombings, local police and federal authorities said Wednesday after a spate of media reports indicated that someone was in custody and headed to court.
As several hundred bystanders, reporters, police and U.S. marshals gathered outside Boston's federal courthouse in anticipation of an arrest, law enforcement officials began escorting people from the building.
"We are evacuating the building," members of the Boston Police Department told the crowd outside the John Joseph Moakley Federal Courthouse, shortly after 3 p.m.
There was no immediate word of why they took the action.
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Around 3:15 p.m., a bomb squad arrived at the courthouse, near the Boston waterfront. Minutes later, reporters on the scene saw civilians filing out of the courthouse and K-9 units walking in.
During the evacuation, vehicles from U.S. Department of Homeland Security pulled up in front of the building. Law enforcement officers carrying long guns stood nearby.
Two possible suspects in the bombings have been singled out in surveillance videos of the scene, sources told the Los Angeles Times on Wednesday.
U.S. counter-terrorism and law enforcement officials told The Times that a department store video caught images of one man leaving a backpack near the finish line. A second federal official said he has been told that authorities believe a second video or photo showed "two men with two backpacks."
A counter-terrorism official said the men were picked out because they were carrying black backpacks, as well as because of their demeanor and how they reacted to the bomb blasts. That official said authorities do not yet know the identities of those in the videos.
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The Boston police were the first to puncture the media arrest reports with a tweet: “Despite reports to the contrary there has not been an arrest in the Marathon attack.”
That was quickly followed by a formal statement from the FBI:
“Contrary to widespread reporting, there have been no arrests made in connection with the Boston Marathon attack,” the FBI said.
“Over the past day and a half, there have been a number of press reports based on information from unofficial sources that has been inaccurate. Since these stories often have unintended consequences, we ask the media, particularly at this early stage of the investigation, to exercise caution and attempt to verify information through appropriate official channels before reporting,” the FBI said.
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CNN and The Boston Globe were among the first to report the arrest. The Associated Press quickly followed with a report that someone was in custody and that something would happen at a courthouse, prompting the crowd and reporters to converge at that building.
The Los Angeles Times published on its website information by the Associated Press stating that an arrest was imminent.
The original arrest reports from various news organizations, including CNN and the the Globe, were attributed to sources and officials who asked not to be named. Both organizations later revised their accounts.