PYEONGCHANG, Korea, Republic Of -- The first doping case of the Pyeongchang Olympics has been announced.

Officials say Japanese short-track speedskater Kei Saito has tested positive for acetalozamide, a diuretic that is also a masking agent which can disguise the use of other banned substances.

The Court of Arbitration for Sport says Saito "accepted on a voluntary basis to be provisionally suspended and to leave the Olympic Village."

Saito did not race in any event before the test result from a pre-competition sample was confirmed. His official blog says he's 21 and was competing in his first Olympics.

CAS says its judging panel handling Olympic doping cases will issue a final verdict after the games are over.

The highest court in world sports handles the prosecution of doping cases, and the International Olympic Committee is responsible for testing athletes.