St. Louis school gunman was armed with AR-15-style rifle and over 600 rounds of ammunition, official

The 19-year-old gunman who killed two people at St. Louis high school Monday was armed with an AR-15-style rifle and over 600 rounds of ammunition, and he left behind a note referring to mass shootings, police said.

St. Louis police on Tuesday showed an image of the rifle used by Orlando Harris, who died after he exchanged fire with authorities.

"He had seven magazines of ammunition on a chest rig that he wore. He also had an additional eight magazines of ammunition in a field bag that he had carried," Police Chief Mike Sack told reporters. "This doesn't include the number of magazines that he left and dumped on the stairway in the corridors along the way."

Sack said the shooting could have been worse had officers not gotten to Central Visual Performing Arts High School as quickly as they did.

“This could’ve been a horrific scene," he said. "It was not, by the grace of God and that the officers were as close as they were and responded in the manner that they did."

Sack, who did not clarify how the shooter got access to the weapon, stressed the importance of checking in with people who are in distress.

“If you're aware of an individual who appears to be suffering from some kind of mental illness or distress and they begin speaking about purchasing firearms or causing harm to others, we encourage you to reach out to somebody and report that so that we can get help to that individual," he said.

The high school and the Collegiate School of Medicine and Bioscience, which share a building, will be closed through Friday. The schools will switch to virtual learning next week while repairs are being made, according to Kelvin R. Adams, superintendent of St. Louis Public Schools.

The gunman also left a handwritten note in the car he drove to the school, police said.

Sack read part of the note at the news conference, in which the gunman described himself as a loner and referred to mass shootings.

"So, in reading this, we could see some of what's going on inside his mind," Sack said. "He feels isolated, he feels alone, quite possibly angry and resentful of others who have what appeared to him to be healthy relationships, and so desired to lash out."

Harris entered the high school at around 9 a.m. Monday with what police at the time categorized as a long gun.

After a gunfight with authorities minutes later, the gunman was taken into custody and pronounced dead later, a St. Louis police official told reporters.

Jean Kuczka, 61, a health teacher, and Alexzandria Bell, 15, a student, were killed in the shooting, officials said.

People gather outside after a shooting at Central Visual and Performing Arts High School in St. Louis on Monday. Jordan Opp / St. Louis Post-Dispatch via AP