Nadezhda Sergeeva has tested positive for a banned heart drug, the Russian Bobsleigh Federation has announced.

The women's bobsleigh pilot is the second athlete representing Olympic Athletes of Russia to be subject of an anti-doping rule violation at the Winter Olympics.

On Thursday Alexander Krushelnitsky was stripped of the mixed doubles curling bronze medal he won with his wife, Anastasia Bryzgalova, the Court of Arbitration for Sport's anti-doping division said. 

The Russian Bobsleigh Federation reported on its official Facebook page that Sergeeva tested positive on February 18, two days before the women's bobsleigh competition in Pyeongchang, having returned a clean sample on February 13.

"The medical staff of the national team did not prescribe the drug to the sportswoman," the Russian Bobsleigh Federation said on Facebook.

"The Russian Bobsleigh Federation and the athlete herself understand the extent of her responsibility and understands how the event may react to the fate of the whole team."

Sergeeva and her brakewoman Anastasia Kocherzhova finished 12th in the women's two-person bobsleigh which took place on Tuesday and Wednesday.