Indian wrestler Narsingh Yadav, who was set to compete at the Rio Olympics in the 74kg freestyle category, has tested positive for a banned steroid, the national anti-doping agency (NADA) told Reuters on Sunday.

Both of the 26-year-old's samples from an out-of-competition test returned positive and the wrestler had attended a hearing to present his case before an anti-doping disciplinary panel on Saturday.

The panel had asked NADA for further details and should return with a verdict within one week, NADA Director General Navin Agarwal said by telephone.

"Narsingh was surprised with the positive result," Agarwal said. "He kept on saying 'why would I volunteer for a test if I knew I had taken something illegal?"

Agarwal said it was too early to say if Yadav's Rio hopes are over.

"The disciplinary panel has sought more details on the case," he said. "It's too early to determine how much time they will take to come out with a verdict.

"But I would say we should know in a week."