The International Olympic Committee formally opened an investigation Thursday that could result in Lance Armstrong being stripped of his Olympic bronze medal.

The IOC is looking into the Olympic involvement of Armstrong, other riders and officials implicated in the U.S. Anti-Doping Agency report detailing "the most sophisticated, professionalized and successful doping program that sport has ever seen."

Cycling's governing body, the UCI, last week formally stripped Armstrong of his seven Tour de France titles from 1999-2005. Armstrong could now also lose the bronze medal he won in the road time trial at the 2000 Sydney Olympics.

"The IOC will now immediately start the process concerning the involvement of Lance Armstrong, other riders and particularly their entourages with respect to the Olympic Games and their future involvement with the games," the International Olympic Committee said in a statement.

Levi Leipheimer, a former Armstrong teammate who won the time-trial bronze at the 2008 Beijing Games, could also have his medal revoked. One of the key witnesses in the USADA's case against Armstrong, the American confessed to doping.

The medals could come up for review at the IOC's executive board meeting next month in Lausanne, Switzerland. Meantime, the IOC is also monitoring the UCI's plans for an independent investigation to examine allegations about the federation's own conduct and relations with Armstrong raised by the USADA report.

"The IOC has taken note of the UCI's decision and welcomes all measures that will shed light on the full extent of this episode and allow the sport to reform and to move forward," the IOC said.

"We await the findings of the independent commission which will look into the UCI's role, and the recommendations they will make to ensure a healthy future for cycling."

In the case of Armstrong's medal, the IOC will have to study whether the eight-year statute for revising Olympic results applies or not.

IOC vice-president Thomas Bach recently told The Associated Press that the USADA report took an "intriguing approach" that leaves the eight-year period open to discussion.

"What we would have to check is whether this would also work under Swiss law or whether we find a way to apply U.S. law," Bach said.

Armstrong finished behind winner and U.S. Postal Service teammate Vyacheslav Ekimov of Russia and Jan Ullrich of Germany. Fourth place went to Abraham Olano Manzano of Spain, who stands to move up to bronze if Armstrong is stripped of the medal.

Finishing fourth behind Leipheimer in 2008 was Alberto Contador, the Spaniard who was stripped of the 2010 Tour de France title after testing positive for clenbuterol.

Leipheimer is currently serving a reduced, six-month suspension after co-operating with the USADA probe. He was fired by the Belgium-based Quick Step team last week "in light of the disclosures."

In August, the IOC stripped Tyler Hamilton — a former Armstrong teammate — of his gold medal from the 2004 Athens Olympics after he admitted to doping. Ekimov was upgraded to the gold.

'Things that need to be done'

In related news, former International Cycling Union board member Sylvia Schenk says the governing body must give enough resources for an independent commission to investigate allegations raised in the Lance Armstrong doping case.

Schenk, the sports adviser for anti-corruption experts Transparency International, told The Associated Press the panel will need help to fulfil the task asked by the UCI, which is seeking to regain credibility within the sport.

"The commission will not be able to do everything itself," Schenk said in a telephone interview. "It must outsource some of the things that need to be done."

UCI president Pat McQuaid acknowledged last month that professional cycling was in its biggest crisis after the U.S. Anti-Doping Agency set out in devastating detail how Armstrong's teams cheated during his 1999-2005 run of Tour de France wins.

After accepting last week that Armstrong should be banned for life and stripped of his race results, the UCI moved to restore its own reputation.

McQuaid said it would create a commission to examine allegations about the governing body's conduct raised by the USADA report, including that Armstrong donated $125,000 in exchange for covering up suspicious doping tests. The UCI wants a report and recommendations delivered by June 1.

Schenk said past explanations about the donations — including exact amounts and when they were paid — had been "contradictory."

"If the UCI discloses everything then it really has a chance to look into details to see who has been involved, and to take measures to kick out those who have been involved," said Schenk, who was an elected member of the UCI board for five years through 2005 under then-president Hein Verbruggen.

Schenk said there is a mood within cycling to change and end the culture of doping.

"Whether it will really happen, that depends in the next four, five, six weeks — whether such a commission is really independent and having resources," the former German cycling federation president said.

The UCI has said it will announce next week which "independent sports body" will nominate the investigation panel members.

The Court of Arbitration for Sport's ruling board is the best candidate for that job, Schenk said.

FIFA also asked Transparency International to contribute, and Schenk submitted a report urging president Sepp Blatter to probe unresolved corruption claims as a fundamental step to rebuilding credibility. She opted out of the reform process last November after questioning its independence.

Schenk said the not-for-profit group could consider making a submission to the cycling commission, which the UCI said will be asked to "find ways to ensure that persons caught for doping were no longer able to take part in the sport, including as part of an entourage."