China’s Chen Xinyi has become the first swimmer to fail a doping test at the Rio Olympics, the Chinese Swimming Association has told state media.
According to the official Xinhua news agency, the 18-year-old tested positive for diuretic hydrochlorothiazide on Sunday.
That was the day Chen finished fourth in the women’s 100m butterfly final.
Chen has applied to the International Olympic Committee for her B sample to be tested and for a hearing.
She is scheduled to compete in the 50m freestyle, which begins on Friday at 17:02 BST.