The US Anti-Doping Agency (USADA) has brought formal doping charges against US cyclist Lance Armstrong and he has been immediately banned from competition in triathlons as a result, the Washington Post reported on Wednesday.
Armstrong, a seven-time Tour de France winner, denied the charges in a statement: "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."
The Post cited a 15-page charging letter by the USADA.
It said the agency, which oversees anti-doping in Olympic sports in the United States, was empowered to bring charges that could lead to suspension from competition and the rescinding of awards but did have not authority to bring criminal charges.
A spokesman for the USADA was not immediately available to comment.
Armstrong said: "These are the very same charges and the same witnesses that the Justice Department chose not to pursue after a two-year investigation."
In February, the U.S. Justice Department dropped an investigation centred on whether Armstrong and his teammates cheated the sponsor of their bike racing team with a secret doping program.
That decision meant that Armstrong, a cancer survivor and one of his sport's greatest champions who has always vehemently denied using performance-enhancing drugs, would not face criminal charges from the two-year-long probe.
At that time, however, the USADA said the end of the Justice Department's criminal probe did not mean the doping agency would not pursue its own course of action.
"Unlike the US Attorney, USADA's job is to protect clean sport rather than enforce specific criminal laws," USADA Chief Executive Officer Travis Tygart said in a written statement at that time. "Our investigation into doping in the sport of cycling is continuing and we look forward to obtaining the information developed during the federal investigation."
Doping, or using performance enhancing substances in professional sports, is not in itself a federal crime.
The Post said it had obtained a charging letter dated June 12, in which the USADA made previously unpublicised allegations against Armstrong. It alleges it collected blood samples from Armstrong in 2009 and 2010 that were "fully consistent with blood manipulation including EPO use and/or blood transfusions."
EPO is erythropoietin, a naturally occurring protein, and its use is one recent way athletes have tried to artificially boost their red blood cell count and athletic performance.
Armstrong has never tested positive.
The Post said the USADA's letter alleges that Armstrong and five former cycling team associates engaged in a doping conspiracy from 1998-2011.
The letter specifically alleges that Armstrong used EPO, blood transfusions, testosterone, corticosteroids and masking agents and that he distributed and administered drugs to others.
The Texas-born cyclist last Tour de France victory was in 2005 and he has since taken up competing in triathlons.
"I have been notified that USADA, an organization largely funded by taxpayer dollars but governed only by self-written rules, intends to again dredge up discredited allegations dating back more than 16 years to prevent me from competing as a triathlete and try and strip me of the seven Tour de France victories I earned.
"These are the very same charges and the same witnesses that the Justice Department chose not to pursue after a two-year investigation. These charges are baseless, motivated by spite and advanced through testimony bought and paid for by promises of anonymity and immunity.
"Although USADA alleges a wide-ranging conspiracy extended over more than 16 years, I am the only athlete it has chosen to charge. USADA's malice, its methods, its star-chamber practices, and its decision to punish first and adjudicate later all are at odds with our ideals of fairness and fair play.
"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.
"That USADA ignores this fundamental distinction and charges me instead of the admitted dopers says far more about USADA, its lack of fairness and this vendetta than it does about my guilt or innocence."