A Bridgeport police officer who accidentally shot himself in the leg in a crowded bagel shop was arrested on a gun charge. State Police said Tuesday that they charged Juan Santiago, 55, of Bridgeport, with unlawful discharge of a firearm in connection with the Dec. 17 incident at the Bagel King on Main Street. Troopers said Santiago was sitting with three other officers when he mishandled a pistol that fired a shot through his left thigh. No one else was injured. Santiago was treated at a hospital. Santiago turned himself in Monday.