|Armstrong has rejected the claims by his former teammate [GALLO/GETTY]
He may have retired from cycling, but the doping rumours still follow him.
In the latest saga in Lance Armstrong's long and glittering career, former US Postal teammate Tyler Hamilton has accused the seven-time Tour de France winner of using the banned drug EPO in the first year he won the race in 1999.
Speaking on America's CBS News show "60 Minutes", which will be shown in full on Sunday, Hamilton said Armstrong took EPO in the 1999 Tour and before the race in 2000 and 2001. EPO (erythropoietin) is designed to increase endurance by boosting production of red blood cells.
"I saw it in his refrigerator," Hamilton said.
"I saw him inject it more than one time like we all did, like I did many, many times."
Hamilton, who was allowed to keep his Athens Olympics gold medal despite failing a doping test, has finally confessed to cheating and accused other top cyclists, including Lance Armstrong, of doing the same.
In the interview Hamilton ended years of denials by finally admitting to using performance-enhancing drugs, but insisted he was not alone.
The 40-year-old said he witnessed his former team mate Armstrong inject himself with a blood-booster during the 1999 Tour de France, which Armstrong won.
"(Armstrong) took what we all took... there was EPO (erythropoietin)... testosterone... a blood transfusion," Hamilton said in an excerpt released by the CBS television network.
Armstrong has steadfastly denied doping and has never failed a drug test.
However, federal authorities are investigating whether Armstrong and his former US Postal team did participate in a systematic doping program.
Hamilton's accusations come a year after Floyd Landis, another former Armstrong teammate, made similar allegations of drug use by Armstrong and the team. And like Landis, Hamilton said Armstrong failed a drug test at the 2001 Tour de Suisse.
His lawyer, Mark Fabiani, told Reuters news agency that Hamilton's accusations about Armstrong were untrue.
"Hamilton is actively seeking to make money by writing a book and now he has completely changed the story he has always told before so that he could get himself on "60 Minutes" and increase his chances with publishers," Fabiani said.
"But greed and a hunger for publicity cannot change the facts: Lance Armstrong is the most tested athlete in the history of sports."
Armstrong spoke out about the allegations on his Twitter page.
"20+ year career. 500 drug controls worldwide, in and out of competition. Never a failed test. I rest my case"
Lance Armstrong's Twitter response
"20+ year career. 500 drug controls worldwide, in and out of competition. Never a failed test. I rest my case," he tweeted.
Hamilton was a support rider of Armstrong's at the US Postal Service team for his first three Tour de France victories.
In 2004, Hamilton won the time-trial at the Athens Olympics and was allowed to keep his medal after testing positive for blood doping because the laboratory accidently destroyed his B sample by deep freezing it.
The following year, Hamilton tested positive for a blood transfusion and was banned for two years.
In 2006 he was linked to the Spanish doping scandal dubbed "Operation Puerto" before testing positive for steroids three years later. He was given an eight-year ban after he said he had taken an over-the-counter treatment for depression.
The 39-year-old Armstrong retired in February after a string of disappointing results.
Armstrong initially retired from cycling after the 2005 Tour de France, but returned to competition in 2009.
He finished third in the 2009 Tour de France and most recently placed 67th in January's Tour Down Under in Australia.