Colorado
A police vehicle sits in front of an entrance to the STEM School Highlands Ranch on May 8, 2019 in Highlands Ranch, Colorado, one day after a shooting there killed one student and injured eight others. Two students were taken into custody following the shooting. (Photo by Michael Ciaglo/Getty Images)

Two students of the Colorado STEM school are in custody after opening fire on campus and injuring eight people during a shooting on Tuesday, officials said.

The Douglas County Sheriff’s Office has confirmed that one suspect is a juvenile male and the other is an adult male.

“Two individuals walked in to the STEM school, got deep inside the school and engaged students in two separate locations,” Douglas County Sheriff Tony Spurlock said.

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Officers were dispatched to the STEM School Highlands Ranch just before 2 p.m. after receiving a call about shots fired, according to NBC News. Several of injured are in critical condition.

“The only thing that we know of right now from one interview is that we have a handgun. Other than that I cannot tell you of other weapons,” said Spurlock.

According to the STEM School Highlands Ranch website: “We are a think tank, a learning lab and a catalyst for creativity. We are a haven for continual innovation, creative exploration, and rigorous discovery. We defy definition and break with convention. Because that’s what innovators do.”

The school boasts about 1,850 students — 550 elementary age, 700 in middle school and 600 high schoolers, according to the district.

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An eyewitness to the shooting, Rocco DeChalk, who lives blocks from the school, told reporters about the chaotic scene outside his home during the shooting.

“I saw all of them running, so I thought it was a gym class at first,” he told NBC News. “But then I saw there were so many of them.”

According to the account of one female student who was caught up in the mayhem, when the shooters entered her classroom, a couple of classmates took them down.

“She said that two of her classmates took the shooters down, and she was able to escape,” the student’s mother, Nyki Giasolli, told KUSA. “She just said there were people shot; that’s all I know.”

Her daughter, who is a senior, and her son, a freshman, were not harmed during the attack, but Giasolli noted, “We chose a small school because we thought they’d be safer, because we thought that everybody would know everybody.”

The campus is located eight miles southeast of Columbine High School, the site of the 1999 mass shooting in which two gunmen murdered a dozen students and a teacher before turning the guns on themselves.