FBI investigators will attempt to reconstruct the bombs used in Monday’s deadly attack near the finish line of the Boston Marathon, which killed three people and wounded more than 170 others.
Pieces of black nylon, possibly from a bag or backpack that contained the bombs, nails and ball bearings have been sent to the FBI’s laboratory “for a complete and thorough analysis,” said Richard DesLauriers, the special agent in charge of the FBI’s Boston office, at a news conference Tuesday.
DesLauriers said investigators would try to reconstruct the explosive devices to determine where they came from.
Sources have told media outlets that the perpetrators of the deadliest attack on American soil since September 11, 2001, used metal pressure cookers, the type found in many American kitchens, to build at least one of the two bombs.
They had stuffed the pressure cooker with explosive powder, nails and ball bearings to inflict maximum damage.
At Tuesday’s news conference, DesLauriers made an impassioned plea to the public for information about the person or people behind the bombings.
“Someone knows who did this,” DesLauriers told reporters.
“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.”
DesLauriers said investigators had received about “2,000 tips” as of midday Tuesday and they would “continue to work around the clock to investigate or act on leads.”
The FBI has asked businesses near the scene of the attack to preserve video surveillance and spectators who captured video, audio or photos of the incident – before and after – to send them to the FBI.
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