Police and investigators work on Boylston Street, near the finish line of Monday's Boston Marathon, in Boston, Wednesday, April 17, 2013. Authorities investigating the deadly bombings at the Boston Marathon have recovered a piece of circuit board that they believe was part of one of the explosive devices, and also found the lid of a pressure cooker that apparently was catapulted onto the roof of a nearby building, an official said Wednesday. (AP Photo/Charles Krupa)
Gallery: Bombing investigations and memorials
Apr. 17, 2013 @ 02:17 PM
BOSTON -- Investigators combed through the scene of Monday's explosions in Boston the victims were remembered with memorials and vigils.