Authorities have reportedly identified an image of a young man carrying – and perhaps dropping – a black bag at the second bombing scene at Monday’s Boston Marathon.
The Boston Globe, citing an official who declined to be identified, said investigators are “very close” in the investigation. Authorities may publicize their finding as early as this afternoon, the Globe reports
A surveillance camera at Lord & Taylor, located directly across the street, has given investigators clear video of the area, according to the unnamed official.
“The camera from Lord & Taylor is the best source of video so far,” said Dot Joyce, a spokeswoman for Boston Mayor Thomas M. Menino told the Boston Globe. “All I know is that they are making progress.”
Fox News has been told that the circuit board suspected of being used to detonate the Boston Marathon bomb has been recovered, and that FBI investigators continue to scan and analyze the cell phone tower records to identify positive hits for signs of calls that may have triggered both explosions remotely.
According to a FBI and Department of Homeland Security bulletin, the evidence at this time supports just one pressure cooker used. Shrapnel in that device included nails, BBs and ball bearings.  The main charge - possibly low explosive - has not been identified.  The other device "was also housed in a metal container, but currently there is insufficient evidence to determine if it was also a pressure cooker. The fuse system and method of initiation for the two devices are unknown at this time."
Pressure cooker bombs have been used in high-profile bombings in India, Pakistan and Afghanistan, and have been touted in the Al Qaeda in Yemen's online propaganda magazine Inspire and in the "The Anarchist Cookbook."
Fox News' Catherine Herridge contributed to this report.