Russia's 4x400m women's relay team was stripped of its London 2012 silver medal on Wednesday after the IOC named one of its athletes as a doping cheat.

Using new technology the International Olympic Committee is retesting hundreds of stored samples from the 2012 and Beijing 2008 Games as part of its drive to clean up the drug-tainted Olympics.

The latest to be snared is Antonina Krivoshapka, a 400m runner who was part of the Russian team that came second in the relay in London.

The IOC said the 29-year-old tested positive for the banned steroid turinabol and it means that the whole Russian 4x400m women's team is disqualified.

The United States won the relay with Jamaica third and Ukraine fourth.

The Russian men's 4x400m relay team that won bronze in Beijing was similarly stripped of its medal because of doping.

Russian athletes were banned from the Rio Olympics last year because of state-sponsored doping and a second Russian, discus thrower Vera Ganeeva, 28, was also disqualified on Wednesday after finishing 23rd in London. She too tested positive for turinabol.

Turkish boxer Adem Kilicci, 30, was also disqualified after ranking fifth in London after he too was found to have taken turinabol, the IOC said.

Last week Usain Bolt lost one of his nine Olympic gold medals when the IOC stripped Jamaica of their 4x100m relay win at the 2008 Games after team-mate Nesta Carter was caught doping.

Source :AFP