Lance Armstrong is facing more doping allegations just a few months after he thought he had finally put them to rest.

Although federal investigators in February closed a two-year investigation without bringing criminal charges, the U.S. Anti-Doping Agency has filed new doping charges that could strip the seven-time Tour de France winner of his victories in cycling's premier race.

Armstrong insists he is innocent.

“I have never doped, and, unlike many of my accusers, I have competed as an endurance athlete for 25 years with no spike in performance, passed more than 500 drug tests and never failed one,” Armstrong said in a statement. “Any fair consideration of these allegations has and will continue to vindicate me.”

The move by USADA immediately bans him from competing in triathlons, which he turned to after he retired from cycling last year. In a letter, USADA said its investigation included evidence dating to 1996. It also included the new charge that Armstrong blood samples taken in 2009 and 2010 are “fully consistent with blood manipulation including EPO use and/or blood transfusions.”

Armstrong came out of his first retirement to race in the Tour de France those two years.

Dismisses allegations

Armstrong, who was in France training for a triathlon, dismissed the latest allegations as “baseless” and “motivated by spite.”

The USADA letter, a copy of which was obtained by AP, accuses Armstrong of using and promoting the use of the blood booster EPO, blood transfusions, testosterone, human growth hormone and anti-inflammatory steroids.

The letter doesn't cite specific examples, but says the charges are based on evidence gathered in an investigation of Armstrong's teams, including interviews with witnesses who aren't named.

Cycling's governing body, the International Cycling Union, which collected the 2009 and 2010 samples cited in the USADA letter, said it was not involved in the anti-doping group's investigation.

According to USADA's letter, more than 10 cyclists as well as team employees will testify they either saw Armstrong dope or heard him tell them he used EPO, blood transfusions, testosterone and cortisone from 1996 to 2005. Armstrong won the Tour de France every year from 1999-2005. During their investigation, federal prosecutors subpoenaed Armstrong supporters and ex-teammates to testify in Los Angeles. One of the most serious accusations came during a “60 Minutes” interview when former teammate Tyler Hamilton said he saw Armstrong use EPO during the 1999 Tour de France and in preparation for the 2000 and 2001 tours.

Armstrong has until June 22 to file a written response to the charges. The case could ultimately go before an arbitration panel to consider evidence.

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