• Brendan Bialy, who helped disarm a shooter at his Colorado high school in May, graduated Marine Corps boot camp in September.
• Bialy enlisted in the Marine Corps Delayed Entry Program as a high school senior and was to enter training before the shooters entered his school that day.
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A teenager known for heroically thwarting the attempt of a gunman to kill scores of students and faculty as he attended class at STEM School Highlands Ranch in Colorado has officially become a United States Marine.

Brendan Bialy was one of three students who lunged at one of two shooters inside the high school wing of STEM in May of this year, effectively disarming him and potentially saving many lives. Bialy, Kendrick Castillo, and Joshua Jones, all seniors at the time with days left until graduation, chose to confront the gunman, also a student at the school, giving others a chance to escape.

"Kendrick lunged at him, 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," survivor Nui Giasolli said of the brave interception. Castillo was shot in the chest by one of the suspected gunman, Devon Erickson, and later died from his injuries. Castillo was the only fatality of the attack, and both gunmen were taken into custody alive.

Bialy, 18, said that his friend Castillo had "died a legend." He said, "He died a trooper. He got his ticket to Valhalla, and I know he will be with me for the rest of my life. Seriously, I love that kid."

Bialy had enlisted as a high school senior into the Marine Corps Delayed Entry Program and was set to enter training before the shooters entered his school that day.

"My thoughts on becoming a Marine were nothing but reinforced after the shooting," he said following his graduation from boot camp. "What I saw that day was complete and total malevolence, bad overcome by good."

A program for the September graduation from the Marine Corps Recruit Depot in San Diego showed that Bialy had been given a meritorious promotion to private first class during training and served as his training platoon's guide.

SEE ALSO: Aspiring Marine among students who reportedly tried to tackle gunman in Colorado school shooting

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