(CN) - Federal prosecutors closed their two-year investigation of seven-time Tour de France champion Lance Armstrong and his team.
Andre Birotte Jr., U.S. Attorney for the Central District of California, said on Friday that a "public announcement concerning the closing of the investigation was warranted by numerous reports about the investigation in media outlets around the world."
Armstrong, a cancer survivor who never has tested positive for a banned drug, was accused by former teammates of using and encouraging his team members to use illegal drugs or techniques, such as blood doping, in which athletes "donate" and store their own blood, then reinject it before a race to increase their body's oxygen-carrying capacity.
The investigation involved prosecutors and special agents with the U.S. Food and Drug Administration, the FBI and the U.S. Postal Service - Office of the Inspector General.
Armstrong, 40, of Austin, told The Associated Press that he was "relieved" that the investigation was over and that he ways was confident he would not be charged.
"It was difficult at times," he said. "But I was confident that we would always end up in this place."
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