American officials have backed Olympic gold medallist Dennis Mitchell in his fight against a ban imposed by the International Amateur Athletic Federation (IAAF) for a positive drugs test.

The USA Track and Field doping hearing board have unanimously agreed that Mitchell did not commit a doping violation, thus clearing the track star to compete in the US. Mitchell (32), was given a two-year suspension by the IAAF in July after concluding that his urine sample from an out-of-competition test at the athlete's home in April had high levels of testosterone and epitestosterone.

Mitchell was delighted with the verdict and declared: "I'm free!"

The IAAF may now review the decision of the doping hearing board, but until then Mitchell is still banned from competing overseas.