A shooting at the St. Louis high school in Missouri on Monday killed three people, including the 19-year-old shooter.

Police said several others were also injured. The chaos broke out when police learned of a shooter in Central Visual and Performing Arts High School at around 9 a.m.

According to NBC News, both the school and the Collegiate School of Medicine and Bioscience in the same building were locked down.

A St. Louis police official told reporters that the suspect was taken into custody after a gunfight with authorities but was later pronounced dead in a hospital.

St. Louis Metropolitan Police Department Interim Chief Mike Sack identified the suspect as Orlando Harris, who graduated from the Central last year with no criminal history. Sack noted that Harris was aggressive and entered the school holding a rifle in a "violent manner."

"There was no mystery about what was going to happen," he said. However, a motive was still not clear.

Sack said the gunman may have had a mental illness but did not provide additional details as the incident is still under investigation.

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What Happened During the St. Louis High School Shooting?

David Williams, a math teacher, said when people heard gunshots, they went into "drill mode," locking doors, turning off lights, and hiding in corners so they would not be seen.

William noted that "someone was trying to open the door," adding that he heard a bang on the door before it shook.

Williams said three shots were fired right after the sound of sirens in the distance, CNN reported. He remembered hearing an adult voice screaming, "You're all going to f***ing die!"

Williams noted that more shots were fired soon after a bullet came in through one of his classroom's windows. He said the officers from the tactical team then showed up, and there was another round of gunfire before he heard a woman telling them that she was a police officer.

He further noted that the whole incident took about 40 minutes and that he and the students ran to an emergency exit. Meanwhile, Sack said the suspect was shot on the third floor, where Williams' classroom is located.

A witness overheard the gunman complain that he was "tired of everybody" in the school. One student also claimed that the pistol jammed at one point, giving children time to flee. 

The police discovered that the suspect had a dozen 30-round ammunition magazines with him. Kimberly M. Gardner, a prosecutor in St. Louis, Missouri, said many people reacted as trained to protect people from getting hurt.

However, Gardner noted that one thing is sure: the lockdown procedures that St. Louis Public School's administrators, teachers, and students at Central Visual and Performing Arts High School followed as this attack unfolded were crucial in preventing further violence.

She added that the situation is still developing, and they will learn more in the coming days.

Victims of St. Louis High School Shooting in Missouri Identified

Authorities did not identify the woman and the teenage girl who died. However, the woman's family revealed to the St. Louis Post-Dispatch that she was Jean Kuczka, a 61-year-old physical education and health teacher.

Kuczka, a mother of five, resided in Jefferson County's Dittmer region. The 16-year-old girl who died was Alexandria Bell. Her family and friends said the sophomore always smiles and loves dance and art.

Sack said seven other teenagers were hurt and rushed to a hospital. He noted that some students had gunshot or graze wounds, some had abrasions, and one had a fractured ankle. Sack said they were now all in stable condition. 

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This article is owned by Latin Post.

Written by: Bert Hoover

WATCH: Recording Captures Gunshots During St. Louis School Shooting - From FOX 2 St. Louis