BOSTON - A lid to a pressure cooker believed to be used in the Boston Marathon bombings was found on a rooftop at the scene.
The FBI confirmed one of the two bombs used in the attacks was made with a pressure cooker. The bombs were packed with explosives, nails, BBs and other lethal shrapnel.
The second device was housed in a metal container, however officials say there is insufficient evidence to determine if it was also a pressure cooker. The FBI and other law enforcement agencies are asking the public to come forward with any information.
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The number of people injured from the bombings now stands at more than 180, and three people have died. Officials still don't know who did it or why.