The suspect in Friday's shooting at a Santa Fe, Texas high school that left up to nine people dead has been identified as 17-year-old Dimitrios Pagourtzis, the Associated Press reported.

Witnesses said the gunman opened fire inside an art class at Santa Fe High School during first period. Explosive devices were also found at the school, authorities said.

Senior Grace Johnson spoke to Dana Perino on "The Daily Briefing" and revealed that she knew the suspect, who was taken into custody.

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Johnson said she was familiar with the "see something, say something" policy, but this student was "not one of those kids" that would have aroused suspicions.

"He was very, very sweet. I had classes with him," Johnson said. "It's really sad, because you don't know why they do this."

Watch Johnson recount the shooting in the clip above.

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