The International Olympic Committee has revealed it will retest 5,000 doping samples from the Beijing Games to check for traces of a new blood-booster drug.
The IOC said its doping lab in Switzerland would be specifically testing for Cera, an advanced version of endurance-enhancing hormone EPO.
The decision comes after French officials detected Cera during retesting of Tour de France samples.
However, it is thought the retests will cover all sports, not just cycling.
IOC president Jacques Rogge explained: "Our message is very clear. The IOC will not miss any opportunity to further analyse samples retroactively.
"We hope that this will work as a strong deterrent and make athletes think twice before cheating."
The decision was welcomed by a number of British winners in Beijing, with three-time champion Chris Hoy describing it as "fantastic news".
OLYMPICS BLOG"I think it is great that significant steps are being taken to try and stop cheating. It is very encouraging," he said.
Bradley Wiggins, who picked up two cycling golds in Beijing, described it as a "brilliant move".
And women's sprint cycling champion Victoria Pendleton added: "If it means that more cheats are caught then that has got to be a good thing."
Olympic 400m gold medallist Christine Ohuruogu said: "If you are a clean athlete you have nothing to worry about.
"It is always good for them to keep finding new ways of catching banned substances.
"It is something that is giving us confidence that they are on the ball. Every athlete wants to know they are competing against people who are not cheating."
Canoeist Tim Brabants, who picked up a gold and bronze in Beijing, said: "I'm all for it because we have got to take every opportunity we can to catch drugs cheats."
The IOC's announcement comes 48 hours after reanalysed samples from the Tour de France using the new technology unearthed two drug cheats - Germany's Stefan Schumacher, a double stage winner on this year's race, and Italian Leonardo Piepoli.
The original urine tests had raised suspicions but proved inconclusive.
"The IOC have a policy that allows them to go back up to eight years to retest a sample, but this is the first time they've done so on this scale," BBC sports news correspondent Gordon Farquhar said.
"What they're looking at is a new test for third generation EPO. It's a blood-boosting drug which allows more oxygen to be carried in the system, therefore aiding stamina.
"At the moment, cyclists from the Tour de France are having their samples retested and already two more have been found to have been cheating using the substance Cera.
"Now the IOC is going to do the same. They will talk to the World Anti-Doping Agency (Wada) to create a protocol for this, which basically means creating a legal format for the retests, so they can go ahead and examine a substantial number of samples."
Andy Parkinson, acting director of UK Sport's Drug-Free Sport team, told BBC Radio 5 Live: "I think this sends a great message, affirming the strong messages the IOC put out before the Games and demonstrating it continues to be committed to anti-doping.
"There was always an expectation that matters wouldn't end with the six positive tests found at the Olympics... and I wouldn't be surprised to see a few more"
The IOC disqualified six athletes for doping during the Beijing Games - Ukrainian heptathlete Lyudmila Blonska, Ukrainian weightlifter Igor Razoronov, Greek hurdler Fani Halkia, North Korean shooter Kim Jong Su, Spanish cyclist Isabel Moreno and Vietnamese gymnast Thi Ngan Thuong Do.
Three other cases are still pending, with Belarusian hammer throwers Vadim Devyatovskiy and Ivan Tsikhan having been given until 17 October provide more information explaining why they tested positive for testosterone.
A decision is due shortly in the case of Polish canoeist Adam Seroczynski, who tested positive for Clenbuterol.
However, Parkinson admits more anti-doping violations are likely following the retests, adding: "All athletes that need high-intensity training would benefit from Cera, and that includes sprinters, long-distance runners, cyclists, Nordic skiers and so on.
"There was always an expectation that matters wouldn't end with the six positive tests found at the Olympics. Already three more are under suspicion and I wouldn't be surprised to see a few more."
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