Chicago police are investigating after a 12-year-old boy allegedly fired a gun he found on a school bus in the city’s Bridgeport neighborhood Monday afternoon. The incident occurred at around 2:25 p.m. along South Wallace Street near West 35th Street. Police said a man left a bag containing a gun unattended on a school bus. A 12-year-old boy discovered the bag, removed the weapon and fired a round, which struck a bus window. No one was injured. #breakingnews #chicago #bridgeport