NOTTINGHAM, MD (RNN) - A 17-year-old high school student is in critical condition after a gunman opened fire in a cafeteria at Perry Hall High School just outside Baltimore around 10:45 a.m. ET Monday.
Officials said the student was the only person injured in the shooting, although other students were treated for emotional trauma. According to CBS Baltimore, the 17-year-old was shot in the back with a shotgun and is being treated at a nearby hospital.
Authorities would not confirm the type of gun used in the shooting, but said they had the firearm in police custody.
The shooting was an "isolated incident," according to Baltimore County Executive Kevin Kamenetz.
"We believe that the suspect fired one round and just struck the individual," Baltimore County Chief Jim Johnson said. "We do not believe he was targeted."
Officials said the suspect has been apprehended after the "heroic" actions of teachers and confirmed he was a student at Perry Hall High School.
The gunman, who students told CBS Baltimore was a 10th grade boy, opened fire in the school cafeteria, striking the 17-year-old. Before he could fire another round, a teacher tackled the boy, forcing his shot into the ceiling.
A school police officer who was on the scene arrested the boy with the help of a number of teachers, who corralled the shooter by a vending machine.
"Student safety is our first and foremost priority," Baltimore County School Superintendent Dallas Dance said. He commended school staff for taking action when the shooter opened fire and added that everyone followed the school emergency plan for active shooter situations.
Students told CBS Baltimore that they were under lockdown for as many as two hours after the shooting.
Parents speaking with CBS Baltimore pointed to a Facebook update that was allegedly posted hours before the shooting. In part, it said "first day of school, last day of my life."
CBS Baltimore declined to name the person who posted the message and officials would not discuss whether there was any connection with the shooting.
Students were evacuated to a nearby shopping center.
The shooting happened on the first day back to school for students in the Baltimore County Public Schools district. The school is the largest in the county with more than 2,000 students.
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