Charges have been filed against a 24-year-old St. Louis man who police say shot and killed a retired police captain during a night of violent protests as the former officer tried to protect his friend’s pawn shop.

Stephan Cannon has been charged with first-degree murder in the death of 77-year-old David Dorn, who was killed on the sidewalk outside Lee’s Pawn and Jewelry early Tuesday.

Police say they have surveillance footage of Cannon at the scene with a gun. Dorn’s death came on a violent night in St. Louis, where four officers were shot and 55 businesses were burglarized or damaged.