The International Olympic Committee said Monday samples taken Aug. 5 and 6 from Ostapchuk indicated the presence of metenolone, an anabolic agent on the 2012 Prohibited List.
Ostapchuk placed first in the women's shot put competition Aug. 6 with a heave of 21.36 meters. New Zealand's Valeria Adams, with a distance of 20.70, was second with Russia's Evgeniia Kolodko (20.48) was third and China's Gong Lijiao (20.22) was fourth.
The IOC's announcement stripped the medal, diploma and medalist pin from Ostapchuk. The ruling makes Adams the gold medalist with Kolodko promoted to a silver-medal finish and Gong given the bronze medal.
Monday's announcement came the morning after the 2012 Olympics wrapped up with Closing Ceremonies in London.
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