The International Olympic Committee (IOC) have revealed that 30 athletes from Beijing 2008 and 15 from London 2012 have tested positive in the second wave of doping retests from the last two Summer Olympic Games.
A total of 23 medallists from Beijing 2008 produced provisional adverse analytical findings as a result of the second wave, which was predominantly focused on athletes who reached the podium in the Chinese capital.
The IOC said that the 30 athletes from the Games came from four sports and eight National Olympic Committees (NOC).
Two sports were implicated in the 15 positives from the London 2012 Olympic Games, coming from a spread of nine NOCs.
The IOC opted to extend their re-testing programme of doping samples from Beijing and London to include all medal winners at the Olympic Summit last month in Lausanne.
It expanded on the targeted re-analysis of athletes due to compete at Rio 2016 completed last month.
A total of 30 tests came back positive in the first wave of testing from Beijing, while 23 were detected from London.
Initially 31 athletes had produced positive samples from Beijing, but the B-samples on two tests came back negative, while a further failed test was also recorded.
After the first two waves of testing, 1,243 doping samples from the Games have now been reanalysed, resulting in 98 positive tests.
A third and fourth wave of re-tests will take place throughout and after the Rio 2016 Olympic Games, with the samples being re-analysed using the latest scientific methods.
The athletes, NOCs and International Federations concerned by the positive drug tests are being informed, the IOC said, with proceedings against the athletes able to commence after B-samples are tested.
"The new reanalysis once again shows the commitment of the IOC in the fight against doping,” claimed Thomas Bach, IOC President.
Today's announcement could be seen as an attempt by the IOC to garner some good press following a spate of doping scandals across sport.
The organisation have been left reeling following the release of Richard McLaren's Independent Commission report into alleged state-sponsored doping by Russia during their home Sochi 2014 Winter Olympics, as well as in competitions in summer sports.
The IOC are currently considering legal options over whether they could implement a blanket ban on the Russian team for Rio 2016.
They have faced calls to make the decision by the World Anti-Doping Agency and 14 National Anti-Doping Organisations.
Ukrainian weightlifter Yulia Kalina was the first athlete to be stripped of her Olympic bronze medal as a result of the first batch of retests.
The International Weightlifting Federation (IWF) stated last month that Federations will be suspended for one year in the event that it is proven the countries produced three or more anti-doping rule violations in the combined re-analysis of samples from Beijing 2008 and London 2012, with Azerbaijan, Belarus, Kazakhstan and Russia potentially facing this threat.