The FBI just released this video footage (above) and these still photos (below) of two suspects in the Boston Marathon bombing.
FBI Special Agent in Charge Richard DesLauriers, who led tonight's press conference, said investigators initially developed a single suspect but now have two. And they need the public's help to find these guys.
The suspect in the white hat is the only one who was actually observed planting a suspected bomb.
Take a close look at these photos and tell the FBI if you recognize either suspect.