The FBI says it is looking for two men in connection with the deadly bombs planted along the Marathon route on Boylston Street: One in a white cap, one in a dark cap. The man in the white cap was last seen heading outbound on Boylston.
Both are to be considered "armed and dangerous," the FBI says.
Photo showing both men walking east at the intersection of Boylston and Gloucester streets:
FBI photos, videos of the two.