An unnamed German biathlete has tested positive for a stimulant at the Sochi Winter Olympics, making it the first doping case at the Games in Russia, a German ski federation official said on Friday.
The official said both of the athlete's samples tested on Thursday and Friday came back as positive for a stimulant.
"We know who is it but we cannot give a name," the federation's Stefan Schwarzbach said.
"As far as I know it is a stimulant that you sometimes find in extra nutrition (nutritional supplements). So, no EPO or things like that."
Earlier, the German Olympic Committee (DOSB) said it had been informed by the International Olympic Committee (IOC) on Thursday evening that a team member had failed a test and a disciplinary commission would convene later in the day after the athlete's B sample was tested.
The athlete, whose name is expected to be announced by the IOC, now faces a possible suspension.
The IOC said before the Olympics it was planning to carry out 2,453 tests during the Games, including 1,269 pre-competition controls, which is a record for a Winter Olympics.
Until Friday no athlete had tested positive for banned drugs at Russia's first Winter Olympics, with the IOC eager to stop cheats from getting to the Games with increased pre-Olympic testing in the months leading up to the event.
The IOC tests all medallists as well as several other finalists for banned substances, while also conducting hundreds more targeted tests based on intelligence.
Drugs-testing vans shadow athletes coming down from the mountains for their medals ceremony in Sochi while athletes can also be tested there for drugs.
After a string of high-profile cases in the past decade, the IOC is eager to prevent the situation where winners who have used drugs still have their moment on the podium before the long and Olympic brand-damaging procedure of stripping medals and re-awarding them.
Samples taken at the Sochi Olympics will also be stored for a decade and re-tested in line with the new World Anti-Doping Code that comes into effect on January 1 2015.
Germany, who are fourth in the medals table with eight golds and 16 medals in total, sent a total of 154 athletes to Sochi.
There were no doping cases during the 1994 Lillehammer Games, none at Nagano 1998 while seven athletes were caught at the 2002 Salt Lake City Olympics and another seven in Turin in 2006. One athlete tested positive at the 2010 Vancouver Olympics.
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