A 29-year-old veteran used a seized truck to drive critically injured victims to safety during what quickly became the deadliest shooting in U.S. history.

Taylor Winston, a Marine veteran from San Diego, was among friends at the Route 91 Harvest festival in Las Vegas Sunday night when a gunman from a nearby hotel room opened fire on the audience. Winston told CBS This Morning he was dancing the two-step with his girlfriend just moments before. Once Jason Aldean stopped playing and the stage went dark, he realized popping sounds he first thought were fireworks were actually rapid-fire bursts of gunfire.

After climbing over a fence to safety, Winston and a friend looked for ways to help those still in danger. Winston checked nearby trucks for keys.

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"First one we tried opening had keys sitting right there. I started looking for people to take to the hospital," Winston told CBS. "There was just too many and it was overwhelming how much blood was everywhere."

Winston told KGTV he looked for victims with the most serious injuries first, loaded them into the truck bed and drove them to Desert Springs Hospital Medical Center. He made two trips before ambulances arrived on scene, CBS reports.

Winston's friends took to Facebook to thank him for his heroism. "You're an outstanding example of what we should all strive to be in time of crisis," Savant Suykerbuyk said, who also said he once served with Winston.

“There’s a lot of unsung heroes that day that stood up and helped people,” Winston told KGTV.

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