The drug tests were part of a large retest by the International Olympic Committee BBC reports .
The International Olympic Committee retested 454 doping samples from the 2008 games in Beijing and 265 from the 2012 London games .
The drug tests were part of a large retest by the International Olympic Committee , which retested 454 doping samples from the 2008 games in Beijing and 265 from the 2012 London games , BBC reports .