The announcement comes after the International Olympic Committee (IOC) retested 454 selected doping samples from the 2008 Games in Beijing.
The IOC said the retests were conducted using the very latest scientific analysis methods.
It also revealed it is awaiting the results of 250 retests from the 2012 Olympics in London.
"All these measures are a powerful strike against the cheats we do not allow to win," IOC president Thomas Bach said.
