The head of the World Anti-Doping Agency believes more Olympic drug cheats will be exposed under a major re-testing programme for a new generation of the blood-boosting drug EPO, called CERA.
The International Olympic Committee is going to retest the 1,000 frozen blood samples from the Beijing Games, and ultimately 4,000 urine samples, following the development of a new test by French laboratories which has uncovered more cheating cyclists from July's Tour de France.
The new test developed to trace EPO CERA was a blood test, so initally only blood samples from Beijing would be retested.
But once a urine test for the substance is available the urine samples will also be tested.
WADA's director general David Howman says it's a significant step in the ongoing war against drugs in sport.
There were only six positive drug tests during the Beijing Olympics.