Former 100-meter world-record holder Asafa Powell and Jamaican teammate Sherone Simpson have each tested positive for banned stimulants, according to their agent.

Paul Doyle told The Associated Press on Sunday that they tested positive for the stimulant oxilofrine at the Jamaican championships and were just recently notified. The news came the same day that American 100-meter record holder Tyson Gay revealed that he also failed a drug test.

Powell helped the Jamaicans to the 400-meter relay gold medal at the 2008 Olympics and was the last man to hold the individual 100 record before countryman Usain Bolt broke it earlier that year.

Simpson won Olympic gold in the women's 400 relay in 2004 and silver in 2012, along with an individual silver in the 100 in 2008.

These doping positives come a month after another Jamaican Olympic champion, Veronica Campbell-Brown, tested positive for a banned diuretic.

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