Five Jamaican athletes, including two Olympic medallists, tested positive for banned performance-enhancing drugs at last month's national championships, sources close to Jamaican athletics told Reuters on Sunday.
The sources said two of the athletes are sprinters while three competed in field events. They said one of the athletes is a junior.
Jamaican Anti-Doping Commission (JADCO) chairman Herb Elliott confirmed the body had received "reports of adverse analytical findings from "A" samples".
"The process of the result management has commenced in accordance with the JADCO Anti-doping rules," he told Reuters.
"We cannot disclose any further information until the athletes have responded to notification of the "A" sample."
Last month Jamaica's most successful female athlete Veronica Campbell-Brown tested positive for a diuretic, which can be used to mask the use of performance-enhancing drugs.
The twice Olympic 200 metres champion has been suspended by the Jamaican Athletics Administrative Association pending the outcome of a disciplinary panel hearing.
Earlier, Jamaica's former world 100 meters record holder Asafa Powell tested positive for a stimulant at last month's national championships, his agent said. Former double sprint world champion Tyson Gay also said he had tested positive for a substance he could not identify and was pulling out of next month's world championships in Moscow.
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