Eaton Square Exchange

(CBS) Pat Tillman was a heroic face of the war on terror - an NFL star who left behind a $3.6 million contract and his new wife to fight for his country after the attacks of Sept. 11. When he died in Afghanistan on April 22, 2004, the Army told his family he’d been killed by enemy fire after courageously charging up a hill to protect his fellow Army Rangers.

But as Katie Couric reports, that story didn’t hold up. He had really been killed by friendly fire, shot accidentally by his fellow soldiers.

For the past four years, his family, led by his mother Mary, has been searching for answers about what really happened, beginning the day she heard the news from Pat Tillman’s wife Marie.

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