A bronze medal winning Russian curler has been charged with a doping offence.
The Court of Arbitration for Sport's anti-doping division said it has begun proceedings against Alexander Krushelnitsky who won bronze in the mixed doubles event along with his wife, Anastasia Bryzgalova, on Tuesday.
The 25-year-old is widely reported to have tested positive for meldonium, a drug which increases blood flow and was found to be used by more than 100 Russian athletes in 2016.
Former world tennis number one Maria Sharapova served a 15-month ban for using the substance after it was added to the World Anti-Doping Agency's prohibited list.
If Krushelnitskiy is confirmed to have tested positive for a banned substance, it will not be the first case of doping at the PyeongChang Olympics after a Japanese short-track speed-skater tested positive for a banned diuretic.
The charge against Krushelnitsky is likely to ignite further debate about the involvement of Russian athletes at the Games.
The Russian Olympic Committee is under suspension by the International Olympic Committee (IOC) following the systemic doping at the Sochi 2014 Olympics.
However, in December, the IOC ruled that Russian athletes who proved they were clean would be allowed to compete as neutrals in the PyeongChang Games, in a team named the Olympic Athletes of Russia (OAR).
The OAR are competing under the Olympic flag and the Olympic anthem is being played at any medal ceremonies they feature in.
There are 168 athletes competing in the OAR team, who have so far won 11 medals, three silvers and eight bronzes - including that won by Krushelnitsky and Bryzgalova.