CNN

The father of a student who was killed Tuesday when he rushed a shooter at STEM School Highlands Ranch said his son saved others because he was selfless.

“Be selfless, that's what my son was, and it got him killed, but he saved others,” John Castillo said of his son, 18-year-old Kendrick Castillo.

John told CNN shortly after the shooting, he and his wife Maria were frantically tying to reach Kendrick on his cell phone, and they were getting more concerned when he wasn’t responding.

“I was a little bit guilty, because as I was trying to call him I thought well maybe this is the wrong thing? Maybe I am putting his life in jeopardy by having the phone ring," John said. "My anxiety and the lump in my chest was growing.”

At the reunification center, John said buses were coming in with children and they were watching the parents reunite with their kids "and we didn’t have that."

John, who is the robotics coach for the school’s team which his son was on, said students kept coming up to them and saying Kendrick saved lives.

"One of the kids told me ‘like a flash, he jumped up.’ She said, ‘You know he’s a hero he saved me, he jumped up and he ran. You couldn’t even see how fast he was running, out the door and after this person to tackle him,’” John said.

His parents were not surprised to hear their son ran into a dangerous situation. “We raised him to be good,” John said.

“Because of what he did, others are alive, and I thank God for that. I love him. And he is a hero and always will be. But there’s another part of you that wishes he just turned and ran, retreated, hid. Did something to put himself our of harms way, if that was possible. But we know Kendrick,” John said. “It’s no surprise that if danger was facing him he would approach it and take it on.”

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