FILE - In this Sept. 26, 2014 file photo, China's Chen Xinyi reacts after winning the women's 50m freestyle swimming final at the 17th Asian Games in Incheon, South Korea. (AP)
A female Chinese swimmer has tested positive for a banned substance at the Rio Olympics, China's swimming association said Friday - the first competitor in the sport to fail a test at the games.
Chen Xinyi tested positive for the diuretic hydrochlorothiazide after she finished fourth in the women's 100-meter butterfly Sunday, missing a bronze medal by nine-hundredths of a second, the Chinese Swimming Association said. Xinhua, China's official state news agency, reported the story Friday.
The 18-year-old also was scheduled to compete in the 50-meter freestyle beginning Friday.
Chen has applied to the International Olympic Committee to have her B sample tested and to get a hearing on the matter, Xinhua said, citing the swimming association.
''The CSA has taken this matter seriously and demanded full cooperation from Chen in the investigation,'' the association said in the statement quoted by Xinhua.
Doping has been a major concern in the Rio Games. Seven Russian swimmers were allowed to compete after initially being banned following reports of a huge, state-sponsored doping operation in their homeland. That decision has sparked complaints from several swimmers, most notably American Lilly King.
Also, Australian gold medalist Mack Horton feuded with Sun Yang over the Chinese star's three-month suspension for using a banned stimulant in 2014. Horton called Sun a ''drug cheat'' after beating him in the 400 freestyle. Sun insisted he was clean and came back to win gold in the 200 free. They will compete again Friday in the preliminaries of the 1,500 free.
No statement about Chen's reported test was posted on the CSA website, and calls to its offices rang unanswered Friday. FINA, the international governing body of swimming, did not immediately respond to a request for comment.
Chen's teammate Wang Shun declined to comment after he won bronze in Thursday's 200-meter individual medley.
''This situation, I don't know the details,'' Wang said.
Li Keke, a spokeswoman for China's national anti-doping agency, said she had no additional information on the Chen case.
''We have noticed media reports about the case. So far the anti-doping agency has yet to receive any official confirmation,'' Li told The Associated Press.
''This reported test should be generated by the organizer. The Olympic committee and FINA should know about it. At present, we will continue to monitor,'' Li said.