Bahrain's Olympic 1,500 metres champion Rashid Ramzi has been stripped of his gold medal for doping at the Beijing 2008 Games, a source within the Olympic movement said on Wednesday.

'Ramzi has been stripped of his gold medal,' the source told Reuters.   

Moroccan-born Ramzi's positive test for the banned blood-booster CERA was announced in April after frozen samples from the Beijing Olympics were re-tested for that specific substance.

The athletes who finished in second, third and fourth place now stand to be upgraded, with the decision resting on the International Olympic Committee (IOC).

Italy's road race silver medallist Davide Rebellin was also stripped of his medal, the source said. Rebellin was ordered to return the silver by Italy's Olympic Committee on Tuesday.

A total of six athletes had initially tested positive for doping after blood sample retests from Beijing were conducted months after the Games.
   

The athletes all had tested positive for CERA, the new generation of erythropoietin (EPO).
   

The IOC retested a total of 948 athletes' samples, focusing mainly on endurance events in cycling, rowing, swimming and athletics.

 Apart from Ramzi and Rebellin, German Stefan Schumacher, already banned for doping, was also confirmed positive as were Greece's 2004 Athens Games 20km walk champion Athanasia Tsoumeleka and Croatian 800 metres runner Vanja Perisic.
   
Dominican Republic weightlifter Yudelquis Contreras initially tested positive but was cleared after her B sample came back negative. The IOC is expected to make an announcement at 1300 GMT.

Nine other athletes tested positive in tests conducted during the Games as well as six horses in the equestrian events.

The IOC conducted the largest ever doping operation with about 5,000 blood and urine tests during the Beijing Games. - Reuters