AMA Supercross and Motocross racer James Stewart has been provisionally suspended by the International Motorcycling Federation after a drug sample tested positive for amphetamines.

The positive test was from the April 12 AMA Supercross round in Seattle. The three podium finishes in the 450 class in Seattle were tested. Ryan Villopoto‘s and Ryan Dungey‘s urine samples were negative for any prohibited substances or any other sign of doping. Stewart’s A sample however, indicated an “adverse analytical finding” of amphetamine. The drug is on the banned substances list in the FIM’s anti-doping code.

Stewart’s suspension begins today, June 20, but he has the right to request and attend the testing of his B sample.

The Yoshimura Suzuki rider is currently competing in the AMA Motocross Championship and the suspension news comes days after Stewart won both motos at the High Point National round in Pennsylvania. After four rounds, Stewart is third in the championship behind KTM‘s Ken Roczen and Dungey.

[Source: FIM]