A classmate of Georgia school shooter Colt Gray said she sat next to the 14-year-old before he committed the horrific massacre and said that at some point He left the classroom and tried to get back in with a gun.

Lyela Sayarath, an 11th-grader at Apalachee High School, told CNN that after Gray left Algebra I class Wednesday morning, he later knocked on the locked door to be let back in.

Another student who was approaching the door “saw he had a gun, so she backed away,” Sayarath added. Gray “then turned toward the classroom, which would have been to my right, and he just started shooting, and you could hear about ten to fifteen shots in a row.”

Sayarath said she and others in her class hid behind desks with the lights off after hearing gunshots.

“When we heard it, most people just dropped to the floor and crawled around in one area like they were stacked on top of each other,” she said. “The teacher turned the lights off, but we all huddled together and I pushed the desks in front of us. I just told people, ‘Pull the desks in front of you, block yourselves, squat down’ – things like that.”

Sayarath described Gray as “calm” and said she was not surprised he was the shooter.

“He never really talked. He was pretty quiet,” she said. “Most of the time he wasn’t there. He just didn’t come to school or skipped classes, but even when he did talk, it was monosyllabic answers and short statements.”

In the incident at Apalachee High School, four people – two 14-year-old students and two teachers – were shot and nine others were injured, authorities confirmed. Gray survived and was immediately arrested. He is expected to be charged with murder and tried as an adult.