London ? The IOC is still uncovering drug cheats eight months after the Beijing Olympics ended.

The International Olympic Committee, staying true to its pledge to fight doping, said Tuesday that six athletes have been nabbed by retesting their blood samples for CERA, an advanced version of the blood-boosting hormone EPO.

A person familiar with the results told The Associated Press the latest tests caught three track and field athletes, two cyclists and one weightlifter.

The person, speaking on condition of anonymity because the names haven’t been released by the IOC, said a male track and field athlete who won only one gold medal was one of the athletes. The other medalist was in cycling.

The IOC did not identify the athletes or sports involved, saying it was notifying the competitors through their national Olympic committees.

U.S. Olympic Committee spokesman Darryl Seibel said the federation hadn’t received notification from the IOC of any adverse findings involving a U.S. athlete.