The IOC said it had disqualified Cao Lei, who won gold in the women's 75kg weightlifting event, Chen Xiexia, winner of the the 48kg event and Liu Chunhong, the 69kg gold medalist from the Beijing Games after testing positive for prohibited substances.
The IOC also disqualified five more athletes, including Nadzeya Ostapchuk, of Belarus, third in the women's shot put competition in Beijing, whose sample was positive for anabolic steroids.
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Re-tests of doping samples from the Beijing and London Games have so far caught 101 doping offenders, with Russia having the most cases.
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