LOS ANGELES - George Hincapie has added his name to the list of ex-Lance Armstrong teammates who say they saw the embattled American cycling hero use performance-enhancing drugs, CBS News reported on Friday.

The American news program "60 Minutes" reported Armstrong's former US Postal teammate Hincapie told federal investigators he witnessed the seven-time Tour de France winner using banned substances.

The "60 Minutes" report comes one day after the network released video of another former US Postal member, Tyler Hamilton, claiming Armstrong cheated during his first Tour de France victory in 1999.

The network is releasing excerpts of the show ahead of the airing of the full program on Sunday. The network did not identify the sources used in the Hincapie report.

"I saw it in his refrigerator," Hamilton told the program. "I saw him inject it more than one time like we all did, like I did many, many times."

Cancer survivor Armstrong won the Tour de France for the first time in 1999 and captured every race from 1999-2005.

Hincapie told federal investigators he and Armstrong used performance-boosting substance EPO and talked about using testosterone to get ready for competitions. Hincapie declined to speak directly to "60 Minutes".

Armstrong has vehemently denied using performance-enhancing drugs during his cycling career.

Armstrong's spokesman Mark Fabiani said on Friday he can't comment.

"We have no way of knowing what is said to a grand jury, so we have no way to comment on these anonymously-sourced reports," Fabiani said.

But Hamilton, who gave up his 2004 Olympic gold medal earlier on Friday, is just the latest in a growing list of former teammates, ex-associates and co-workers to accuse Armstrong of cheating.

In 2010, former teammate Floyd Landis launched a series of damning allegations against Armstrong, with whom he rode in the US Postal team for several years, claiming Armstrong had used banned substances throughout his career.

Armstrong has set up a website to try and discredit his critics but it will be much harder for him to go on the attack against Hincapie. In an interview last year, Armstrong described Hincapie as "like a brother to me".

Armstrong has not spoken directly to reporters this week although he has used his social networking Twitter page to proclaim his innocence. He did not say whether he would try to launch a fresh lawsuit against Hamilton or others who are speaking out.