An informed law enforcement source told the Associated Press that authorities were preparing on Wednesday to take into custody a suspect in the Monday bombings at the Boston Marathon.
While some news organizations reported that a suspect had been detained by early afternoon, Reuters and other news organizations reported that a suspect was known but had not been taken into custody. More information was expected later Wednesday afternoon.
The reports came after the Boston Globe reported that investigators had found a video image that appears to show a person in possession of a bag, and possibly leaving it, at the site of the second explosion near the race finish line.
Authorities by Wednesday had more detail about the two bombs that exploded in quick succession, Reuters reported.
Investigators were examining cloth and metal scraps -- including the remains of ball bearings and nails and what appeared to be a pressure cooker -- for insight into the nature and perpetrator of the strikes that killed three and injured close to 200. An FBI official said investigators had gathered evidence at a facility at Quantico, Va.
CNN reported on Wednesday that the top of a pressure cooker was found on the roof of a building close to the attack site.
One source told AP that one device involved a pressure cooker loaded with metal chunks and ball bearings, while another cooker was filled with nails.
An informed police insider said authorities were examining the possibility that the explosives had been constructed near the site of the attack, the Wall Street Journal reported. Area and national government personnel were searching temporary lodging in the area for hints about the devices' origin.
Nothing suggests the strike was part of a plan involving additional potential attacks, Reuters quoted Homeland Security Secretary Janet Napolitano as saying on Tuesday.