An armed former student broke into a St. Louis high school Monday morning warning, “You are all going to die!” before fatally shooting a teacher and a teenage girl, and wounding six others before police killed him in an exchange of gunfire.

The attack just after 9 a.m. at Central Visual and Performing Arts High School forced students to barricade doors and huddle in classroom corners, jump from windows and run out of the building to seek safety. One terrorized girl said she was eye-to-eye with the shooter before his gun apparently jammed and she was able to run out.

Speaking at a news conference, Police Chief Michael Sack said fast actions by a security guard, along with police officers who “ran to the gunfire” helped end the shooting before more people were killed or hurt. Police on Monday evening identified the shooter as 19-year-old Orlando Harris, who graduated from the school last year. Police said they did not have a possible motive. They said earlier in the day that it was not clear if anyone had been targeted.

Sack said Harris had no prior criminal history.

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