A Thanksgiving night shooting at Alabama’s largest enclosed mall left a gunman dead and two people — including a 12-year-old girl — injured, authorities said, and sent terrified shoppers running for safety. The incident at the Riverchase Galleria in the Birmingham suburb of Hoover started with a fight between an 18-year-old and the 21-year-old gunman, police said. Police do not know how the confrontation began, but “we do not believe at this point the 18-year-old was armed,” Hoover police Capt. Gregg Rector said. The gunman opened fire, shooting the teen twice in the torso, according to police. An armed Hoover police officer who was working security at the mall confronted the gunman as he ran away from the scene and fatally shot him, police said. A 12-year-old girl described by police as a bystander also was shot once, but it’s unclear by whom, Rector said. Both of the injured were taken to hospitals. The girl has had surgery and “does not have life-threatening injuries,” Rector told CNN. Her condition was stable Friday morning, police said. The injured 18-year-old was in serious condition when an ambulance took him to the hospital, police said.