Tillman walked away from a career in the NFL to volunteer for duty in Afghanistan. In 2004, just two years after he enlisted, Tillman was killed. He was 27.

Originally, TIllman's death was reported as coming during an ambush on a coalition combat patrol, but a later investigation revealed that Tillman was killed by friendly fire when one allied group accidentally fired upon another. Tillman received a Silver Star and a Purple Heart, among other awards.

He was a true American hero.

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