Later Tuesday, the Anti-Doping Division of the Court of Arbitration for Sport (CAS) released information on the test, citing acetalozamide as the illegal substance. Acetalozamide can be a masking agent and is used as a diuretic.
Saito was tested after training on Feb. 4, as he was preparing for bed in the Athletes’ Village in Gangneung, according to the Japanese Olympic Committee. The Japanese short-track team arrived in Korea only that day.
Saito has left the Olympic Village and agreed to a provisional suspension, but also issued a strong denial and vowed to fight to clear his name.
The positive test recorded by Saito, 21, is the first ever by a Japanese athlete at the Winter Olympics. Saito was a reserve on Japan’s 5,000-meter men’s relay team, which competes during Tuesday's short-track session at Gangneung Ice Arena.
His sister, Hitomi Saito, is also on the Japanese short-track team.
As we reported earlier, Russian Olympic athletes are competing as Olympic Athletes from Russia.