The International Olympic Committee reported 45 new doping failures on Friday, July 22 from the 2008 Games in Beijing and London 2012, bringing the total number of positive drug test to 98 since a retesting program was launched, AFP reports.

The IOC, facing one of its worst ever doping crises that could see sporting powerhouse Russia banned from the Rio Games, has reanalyzed more than 1,200 samples, with the emphasis on past medal winners.

Reporting results from its second wave of retests, the IOC said there were 30 "Provisional Adverse Analytical Findings" from competitors in Beijing 2008 and 15 "Adverse Analytical Findings" among London 2012 Olympians.

Within the Beijing group, 23 were medalists. The 30 positive results came from eight countries and four sports.

The second wave of retests from London included 138 samples. The 15 positive tests were from nine countries and two sports, AFP says.

The IOC noted however that a provisional finding can be reversed on closer examination. Two provisional positives from the first wave of Beijing tests announced in May were ultimately not deemed conclusive.

"The new reanalysis once again shows the commitment of the IOC in the fight against doping,” Olympics president Thomas Bach said in a statement.

The IOC has said the retesting program followed "intelligence-gathering" that began last year.

The IOC was not able to identify the athletes concerned, citing legal reasons.