Lance Armstrong Doping Claims Heat Up on Eve of '60 Minutes' Exposé (Video)

George Hincapie has told federal authorities that he also saw the seven-time Tour de France winner using performance-enhancing drugs.

Former teammate Tyler Hamilton isn't the only one who says seven-time Tour de France winner Lance Armstrong, who has never tested positive in tests, used performance-enhancing drugs.

George Hincapie has told federal authorities that he also saw Armstrong use PEDs, the Associated Press reports.

Hincapie, who was a longtime member of Armstrong's U.S. Postal Service team, has often been portrayed as one of the cyclist's most loyal teammates, having been with Armstrong for all seven of his Tour victories.

Hincapie is one of several of Armstrong's ex-teammates, including Hamilton, and employees who have appeared before a federal grand jury investigating doping in cycling.

Sources told 60 Minutes that Hincapie testified that he and Armstrong provided each other with a PED that boosted endurance, EPO, and talked about using another illegal substance, testosterone, for race preparation. 

Hincapie had declined to give an interview with 60 Minutes, which airs its news piece on the Armstrong investigation on Sunday at 7 p.m. on CBS. He released a statement later through his lawyer to the AP: "I can confirm to you that I never spoke with 60 Minutes. I have no idea where they got their information. As I've said in the past, I continue to be disappointed that people are talking about the past in cycling instead of the future. As for the substance of anything in the 60 Minutes story, I cannot comment on anything relating to the ongoing investigation."

Armstrong pulled out of an interview with 60 Minutes to defend himself, telling the Daily Beast that the network "basically reneged" on promises it made to him and that "everyone would be frustrated" to be treated like that.

Former Bill Clinton strategist Mark Fabiani has created a website for Armstrong to deny the allegations:

Hincapie and Hamilton's allegations follow Floyd Landis' claim that he and Armstrong had used drugs while on the U.S. Postal team. Though Armstrong has pointed out that Hamilton and Landis have issues of credibility, calling Hamilton a "liar in search of a book deal" on the newly formed website, Hincapie has never tested positive.

Watch a preview of the 60 Minutes piece below: