"I saw Lance Armstrong using drugs," Landis told ABC's Nightline in an interview for Friday night's show, adding that he received the banned substance EPO, as well as other drugs, from the seven-time Tour de France champion.
"Lance Armstrong handed me some testosterone patches," Landis said, adding that he saw Armstrong receiving multiple blood transfusions; another banned practice that boosts a cyclist's endurance.
Landis confessed earlier to doping, and said he witnessed widespread cheating on Armstrong's US Postal Service teams when he was a member from 2002-04.
Landis is also cooperating with the government in a federal grand jury investigation of possible doping conspiracies on Armstrong's teams, the Daily News reports.
"Look, at some point, people have to tell their kids that Santa Claus isn''t real. I hate to be the guy to do it, but it's just not real," Landis said.
Armstrong's attorney, Tim Herman, fired back with a denial of Landis' claims, saying Armstrong is "an athlete that comes along once every couple of generations."
"He is extremely focused. He's gifted physically in ways that are very unique and he is disciplined, dedicated. He's the hardest-working athlete I''ve ever been around. ... Landis is a confessed perjurer and he is a liar," the attorney added.
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