Jamaica
Jamaican sprinter Nesta Carter has been found guilty of doping at the 2008 Beijing Olympics.
It means the 4×100 metres relay team that included Usain Bolt have been stripped of their gold medals.
Bolt completed an unprecedented ‘triple triple’ at the Rio Games last summer but he is now left with eight Olympic titles instead.
31-year old Carter was one of some 450 selected doping samples that were retested by the IOC as the organisation continues its crack down on doping.
His sample has been found to contain a banned stimulant.
Trinidad & Tobago have now been awarded the 2008 relay gold while Japan and Brazil have been upgraded to silver and bronze respectively.
The IOC has also stripped Russian Tatiana Lebedeva of her long jump and triple jump silver medals from the Beijing Games after she tested positive for a steroid.
The IOC program of revisiting samples uses developments in testing techniques to find traces of drugs that were undetectable in 2008 or at the London 2012 Games.
More than 100 athletes have so far tested positive in re-tests from the Beijing and the London Olympics.
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