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When an expelled former student opened fire at Marjory Stoneman Douglas High School in Parkland, Florida, on Feb. 14, Peter Wang used the last minutes of his life to help save his fellow students.

According to witnesses, the 15-year-old freshman member of the school’s JROTC program “was holding a door to let other students out before him” as suspected shooter Nikolas Cruz prowled the halls of his former alma mater, the South Florida Sun-Sentinel reports.

Wang was among the 17 people shot and killed by Cruz. His cousin, Lin Chen, told the Sun-Sentinel that Wang was wearing his standard grey JROTC shirt when he left for school that fateful morning.

Peter WangJesse Pan/Facebook

“He is so brave,” Chen told the newspaper. “He is the person who is genuinely kind to everyone. He doesn’t care about popularity. He always liked to cheer people up. He is like the big brother everyone wished they had.”

Wang was one of several JROTC students who worked to protect their classmates during the shooting. Seventeen-year-old Colton Haab and his fellow JROTC members hid between 60 and 70 students with Kevlar sheets normally used as marksmanship training backdrops to shield them from gunfire.

Broward County Public High School system’s JROTC program boasts an average enrollment of 7,650 students in 28 of its 34 schools annually, and Wang and Haab’s responses speak to the discipline and decisiveness they likely learned there. As Haab told CNN: He “ thinking about how I’m going to make sure everyone goes home to their parents safely.”

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