ASTANA, Kazakhstan -- Four-time Olympian Alexei Poltoranin was among five skiers arrested in Austrian police raids targeting an alleged doping network centered on a doctor who once worked with Tour de France cyclists.
Poltoranin, who has won two world championship medals, did not start the 15-kilometer race at the world championships after Wednesday's raids.
The Kazakh Olympic Committee said Thursday that Poltoranin had been arrested. Samal Nauryzova, a spokeswoman for the Kazakh cross-country ski federation, said "we will defend our athlete," adding the federation is waiting to see proof.
According to the Austria Press Agency, Austrian ski federation official Markus Gandler told ORF television that Max Hauke and Dominik Baldauf were also arrested. Hauke and Baldauf work for the Austrian police, according to a recent interior ministry news release congratulating them on finishing in sixth place in the team sprint at the worlds.
The other two athletes suspected of involvement in the doping ring are Estonian teammates Karel Tammjarv and Andreas Veerpalu, the Estonian ski federation said in a statement.
Veerpalu, who competed at last year's Olympics, is the son of the two-time Olympic gold medalist Andrus Veerpalu, who was acquitted of a doping charge in 2013 by the Court of Arbitration for Sport.
In that case, the CAS panel ruled that "there are many factors in this case which tend to indicate" that Andrus Veerpalu had taken human growth hormone, but the testing procedure wasn't reliable enough for a guilty verdict.
The doctor at the center of the case is Mark Schmidt, who worked for the Gerolsteiner cycling team around the time Austrian rider Bernhard Kohl was stripped of third place at the 2008 Tour de France for doping.
Schmidt was arrested on Wednesday in Erfurt, Germany, where he has a medical practice.
The remaining three people arrested Wednesday by Austrian and German authorities were described by Austrian officials as the doctor's associates. The case could spread to other sports, Austrian officials said.