Olympic cross-country skiing champions Julia Chepalova and Yevgeny Dementiev retired on Tuesday, a day after it was announced they tested positive earlier this year for the banned blood-boosting hormone EPO.

The athletes notified the Russian Ski Federation that they were retiring, federation president Vladimir Loginov said.

But the decisions to retire, "regardless of whether they were taken before or after the official announcement [of the doping violations], do not absolve them of responsibility," Loginov said. "Both will be disqualified.

A third Russian skier, Nina Rysina, who tested positive also for the same banned endurance-boosting hormone during a competition in France on Jan. 27, asked for her B sample to be tested.

On Monday, the International Ski Federation told the Russian federation that Chepalova and Dementiev tested positive during the Tour de Ski at Val di Fiemme, Italy, on Jan. 2-3.

Chepalova, 32, won gold medals at the Winter Games in 1998, 2002 and 2006. She was also the world champion in 2001 and 2005, and won the World Cup in 2001.

Dementiev, 26, was the 2006 Torino Olympics champion in duathlon.

On Aug. 12, the International Biathlon Union suspended three Russians for two years each after finding them guilty of anti-doping rule violations.

Albina Akhatova, Yekaterina Iourieva and Dmitri Yaroshenko tested positive for EPO, during a World Cup last December in Ostersund, Sweden.

"Unfortunately, this doping 'infection' has spread too deep," Loginov said. "We have no chance to check everyone every day or even every minute, even on the national team. But at the end of the investigation the necessary decisions will be taken."