JUST IN: Three People, Including Shooter, Dead in St. Louis High School Shooting

Three people were shot and killed at a St. Louis high school on Monday.

The shooter, around 20 years old, according to interim Police Commissioner Michael Mack, is also dead.

Mack did not release any names.

The shooting reportedly started around 9 a.m. CT. Police responded “without hesitation” and went into Central Visual and Performing Arts High School, where they shot the gunman, who later died while being transported to the hospital. The school is a magnet school.

“When police arrived, students were running out of the school and telling police officers that the shooter had a ‘long gun,’ Mack said, according to Reuters.

According to the St. Louis Post-Dispatch:

School doors were locked Monday morning and there were seven security workers on site, police said, but they would not indicate how the shooter got inside the building.

David Williams, a math teacher at the school, said the school principal came over the loudspeaker around 9 a.m. and said the code word that indicates a school shooter in the building. Williams heard multiple shots outside his classroom, and one of the windows on the classroom door was shot out. He then heard a man say, “You are all going to (expletive) die.”

Taniya Gholston, a 16-year-old student, told the Post-Dispatch she and the shooter saw each other.

“All I heard was two shots and he came in there with a gun,” she said. “And I was trying to run and I couldn’t run. Me and him made eye contact but I made it out because his gun got jammed. But we saw blood on the floor.”

Watch above via CNN.