ST. LOUIS — 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 seven 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 Monday afternoon, police Chief Michael Sack identified the shooter as 19-year-old Orlando Harris, who graduated from the school last year.

Sack said the motive was still under investigation but "there's suspicions that there may be some mental illness that he's experiencing." Investigators later searched Harris' home, Sack said.

Authorities didn't name the victims, but the St. Louis Post-Dispatch identified the dead teacher as Jean Kuczka. Her daughter said her mother was killed when the gunman burst into her classroom and she moved between him and her students.

"My mom loved kids," Abbey Kuczka told the newspaper. "She loved her students. I know her students looked at her like she was their mom."

Sack said the other fatality was a 16-year-old female who died at the school.

Seven other 15- and 16-year-old students, four boys and three girls, were all in stable condition. Four students suffered gunshot wounds or graze wounds, two suffered bruises and one had a broken ankle.

Sack declined to say how Harris was able to get into the building, which has security guards, locked doors and metal detectors.

"If there's somebody who has a will, they're going to figure out, we don't want to make it easy for them," Sack said. "We just got to do the best we can to extend that time it takes them to get into the building to buy us time to respond."

Harris had the gun out when he arrived at the school and "there was no mystery about what was going to happen. He had it out and entered in an aggressive, violent manner."

Harris had nearly a dozen high-capacity magazines of ammunition with him, Sack said. "That's a whole lot of victims. ... It's certainly tragic for the families and it's tragic for our community but it could have been a whole lot worse."

St. Louis Schools Superintendent Kelvin Adams said seven security guards were in the school at the time of the attack, each stationed at an entrance of the locked building. One of the guards noticed the gunman trying unsuccessfully to get in at a locked door. The guard notified school officials, who contacted police.

Sack said the call about a shooter came in at 9:11 a.m. and officers arrived and had Harris down by 9:25 a.m. He and others praised the quick response of officers and other emergency responders.

Central Visual and Performing Arts shares a building with another magnet school, Collegiate School of Medicine and Bioscience. Central has 383 students, Collegiate 336.

Monday's school shooting was the 40th this year resulting in injuries or death, according to a tally by Education Week — the most in any year since it began tracking shootings in 2018. The deadly attacks include the killings at Robb Elementary School in Uvalde, Texas, in May, when 19 children and two teachers died. Monday's St. Louis shooting came on the same day a Michigan teenager pleaded guilty to terrorism and first-degree murder in a school shooting that killed four students in December 2021.

Taniya Gholston said she was saved when the shooter's gun jammed as he entered her classroom. "All I heard was two shots and he came in there with a gun," the 16-year-old told the Post-Dispatch. "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."

Two teachers recounted near-miss confrontations with the shooter.

Ashley Rench told The Associated Press she was teaching advanced algebra to sophomores when she heard a loud bang. Then the school intercom announced, "Miles Davis is in the building."

"That's our code for intruder," Rench said.

Students took refuge beneath her desk and behind her podium as the shooter tried to enter the locked classroom before giving up and going away.

"I don't know why he chose not to break my windows or shoot through the lock," she said.

Raymond Parks was about to teach a dance class for juniors when a man dressed in black approached. At first, Parks thought the man was carrying a broom or a stick. Then he realized it was a gun.

"The kids started screaming and running and scrambling. He walked directly into the two doors and pointed the gun over at me because I was in the front," Parks said.

For some unknown reason, Parks said, the shooter pointed the gun away from him and let Parks and the dozen or so students leave the room. "That's what I don't understand. He let me go," Parks said.

Janay Douglas' 15-year-old daughter got stuck in a hallway when the school was locked down. Douglas said she received a call from her daughter letting her know she heard shots.

"One of her friends busted through the door, he was shot in the hand, and then her and her friends just took off running. The phone disconnected," Douglas said. "I was on my way."

Kuczka, the slain teacher, taught health at Central for 14 years and recently began coaching cross-country at Collegiate, her daughter said. "She was definitely looking forward to retirement though. She was close," Abbey Kuczka said.

Kuczka's biography on the school website said she was the married mother of five and a grandmother of seven. She was an avid bike rider and was part of a 1979 national championship field hockey team at what is now Missouri State University.

"I cannot imagine myself in any other career but teaching," Kuczka wrote on the website. "In high school, I taught swimming lessons at the YMCA. From that point on, I knew I wanted to be a teacher."

The shooting left St. Louis Mayor Tishaura Jones shaken.

"Our children shouldn't have to experience this," Jones said. "They shouldn't have to go through active shooter drills in case something happens. And unfortunately that happened today."

White House press secretary Karine Jean-Pierre said additional action is needed to stop gun violence.

"Every day that the Senate fails to send an assault weapons ban to the president's desk or waits to take another common sense actions, is a day too late for families and communities impacted by gun violence," Jean-Pierre said.

The school district placed all of its schools on lockdown for the remainder of the day, and canceled all after-school activities, including sports.