A gunman broke into a St. Louis high school, shooting a woman and a teenage girl and wounding six others before police killed him in a shootout, the AP reported.

Police Commissioner Michael Sack said the shooter was in his early 20s, but did not give his name or his victims. He declined to say whether the woman who was killed was a teacher.

St. Louis School Superintendent Kelvin Adams said there were seven guards at the school at the time of the shooting, each at the entrance to the locked building. One of the guards noticed a man trying to enter the locked door but failing. According to Sack, the guard notified management and contacted police. He declined to say how the man eventually got inside.