Investigators have several pieces of evidence believed to be part of the homemade explosive devices used in Monday’s bombing at the Boston Marathon.
By examining the physical remnants found at the scene and pouring through a mountain of photos and video of the event, authorities will to attempt to identify who placed the bombs near the finish line.
Photos of the crime scene show the remains of a pressure cooker, a shredded black backpack, pieces shrapnel, a battery, and a partial circuit board.
U.S. Government via ReutersOn Wednesday morning CNN reported, citing a law enforcement source, that investigators have found the lid to a pressure cooker on one of the rooftops in the area — which could hold a number of clues for technicians.
The agency said that a metal container hidden in a backpack also housed the second bomb, but there’s not enough evidence to determine whether it was also a pressure cooker.A law enforcement official told CNN that the bombs were likely detonated by timers connected to the circuits and batteries, but the FBI said they haven’t figured out the detonating system or what exactly set them off.
U.S. government via Reuters
Technicians at FBI’s national laboratory in Virginia will now try to reconstruct the devices using fragments of the pressure cooker, nails, and nylon bags in addition to the type of circuitry and batteries found at the scene.
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