Kendrick Castillo - only days from graduation - acted fast inside of his British literature class at a suburban Denver school Tuesday afternoon. And he paid with his life.
When a gunman burst through the door at STEM School Highland Ranch, barking at students to stay in place and not move, Castillo, 18, rushed the shooter. It was a quick-thinking move that fellow students said gave them a chance to bolt for safety or take cover under desks.
"Kendrick lunged at (the gunman), and he shot Kendrick, giving all of us enough time to get underneath our desks, to get ourselves safe, and to run across the room to escape," senior Nui Giasolli told NBC News on Wednesday morning. Other students helped Castillo tackle the shooter, classmates said.
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Douglas County Coroner Jill Roman confirmed Wednesday that the student killed was Castillo, the sheriff's department said in a tweet.
An emotional John Castillo lauded his kind-hearted son as a hero. "I want people to know about him," he told ABC News.
Castillo, a member of a Highlands Ranch robotics club called FRC 4418 Impulse, was set to graduate Friday, according to media reports, and was described as someone captivated by engineering.
"We're heartbroken by the death of Kendrick Castillo, a victim of the STEM School Highlands Ranch shooting," tweeted FIRST, a youth non-profit that advances STEM education. "Kendrick was a member of @Frc4418, of which his father is Lead Mentor. Our hearts go out to Kendrick's family, friends, & all affected by the shooting."
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Castillo had been a four-year member of the school's robotics team and had several technology internships, according to his LinkedIn page, Buzzfeed reported.
Rachel Short of Bacara USA, a manufacturing business where Castillo began an internship last year, said he performed so well the company gave him a part-time job. Short said Castillo loved engineering and was eager to help people.
"To find he went down as a hero, I'm not surprised,'' said Short, the company's CEO. "That's exactly who Kendrick was."
Douglas County Sheriff Tony Spurlock said investigators had not yet determined a motive for the attack that erupted shortly before 2 p.m. local time on Tuesday.
Two people were taken into custody, an 18-year-old male and a juvenile girl, the sheriff's department said.
The shooters were armed with at least two handguns and entered through a middle-school entrance at the K-12 school specializing in math and science, Spurlock said. Eight others were injured.
Contributing: The Associated Press
This article originally appeared on USA TODAY: Kendrick Castillo, hero killed in Colorado school shooting, was days away from graduation