Three Olympic gold medals and one silver medal were stripped on Friday from athletes caught in the latest round of positive doping retests from the 2008 and 2012 Summer Games.
Seven athletes from Belarus, Azerbaijan and Kazakhstan were retroactively disqualified after testing positive for steroids in a reanalysis of their stored doping samples, the International Olympic Committee said.
The IOC, which stores samples for 10 years, reanalyzed more than 1,000 samples from the 2008 Beijing Games and 2012 London Olympics with improved techniques that can detect the use of steroids going back weeks and months, rather than days.
Weightlifter Ilya Ilyin of Kazakhstan was formally stripped of two gold medals - one each from the Beijing and London Games, both in the 94-kilogram class. He is believed to be the first summer Olympic athlete to lose two golds for doping.
The Kazakhstan Olympic Committee had announced Ilyin's sanction on Wednesday. The IOC said in Friday's statement that he tested positive for stanozolol on his Beijing sample and for stanozolol and turinabol in his London test.
In comments reported Wednesday by Kazakh media, Ilyin said he was "shaken" and "in shock" at the news and was considering an appeal. Ilyin is one of the biggest names in weightlifting, and the only athlete to win two Olympic gold medals for Kazakhstan.
Kazakhstan's weightlifting program, which had been one of the world's most successful over the last 10 years, has been almost wiped out by the retesting, with all five gold medals won by Kazakh lifters in 2008 and 2012 now stripped.
Oksana Menkova of Belarus was stripped of the Beijing gold medal in the women's hammer throw after her retested samples came back positive for turinabol and oxandrolone, the IOC said. She also was disqualified from the London Games, where she finished seventh after testing positive for turinabol and stanozolol.
Natalia Mikhnevich of Belarus was stripped of the silver medal in the women's shot put from Beijing after her samples were reanalyzed and tested positive for methandienone and stanozolol, the IOC said.
Mikhnevich joins her husband, Andrei, in being stripped of shot put medals from Beijing. He lost his 2008 bronze medal when he was caught for doping in retests of samples from the 2005 world championships.
While Andrei Mikhnevich is serving a life ban, Natalia also now faces a life ban for a second doping offense. She served a two-year doping ban in 2013-15.
Also sanctioned Friday were: Pavel Lyzhyn of Belarus, fourth-place finisher in the men's shot put in Beijing; Svetlana Usovich of Belarus, eliminated in the semifinals of the women's 800 meters in Beijing; Boyanka Kostova of Azerbaijan, fifth place in the women's 58-kg weightlifting division in London; and Anastasia Mironchuk-Ivanova of Belarus, seventh in the women's long jump in London.
No final decision has been made on reallocation of medals.
Szymon Kolecki of Poland is in line to inherit Ilyin's weightlifting gold from Beijing, while Saeid Mohammedpour of Iran could take his 2012 gold.
Miankova's hammer gold medal could be awarded to Yipsi Moreno of Cuba, with Zhang Wenxiu of China in line to be upgraded to silver and Darya Pchelnik of Belarus to bronze.
The reallocation of medals in the Beijing women's shot put is complicated by the fact that another Belarusian, Nadzeya Ostapchuk, won the bronze. Ostapchuk was stripped of the London gold medal after testing positive at those games.
The IOC recorded at least 98 positive tests across numerous sports from the London and Beijing retesting program, with more expected in the pipeline. The IOC also plans to retest samples from the 2014 Sochi Winter Games after the former Russian lab director said samples were manipulated to cover up doping by Russian athletes.