A source told CNN on Wednesday that the individual was discovered after FBI pored over video from a department store near the site of the second explosion, along with video from a Boston TV station.
Although there have been conflicting reports, investigators do not have the person’s name and no one has been taken into custody at this point.
According to an FBI joint intelligence bulletin, one of the bombs was encased in a pressure cooker hidden inside a backpack and may have contained nails, BBs and ball bearings. The second bomb was also housed in a metal container, but it was not clear whether it was a pressure cooker, said the FBI.
The bombs, which exploded 12 seconds apart, killed three people and wounded 183.
UPDATE: The FBI released this statement: "Contrary to widespread reporting, no arrest has been made in connection with the Boston Marathon attack. Over the past day and a half, there have been a number of press reports based on information from unofficial sources that has been inaccurate. Since these stories often have unintended consequences, we ask the media, particularly at this early stage of the investigation, to exercise caution and attempt to verify information through appropriate official channels before reporting."
There are reports that authorities have identified a suspect in the Boston Marathon bombings, while Justice Dept. officials and Boston PD have denied that a suspect has been arrested.