Italian police staged a late-night raid on the Austrian biathlon team's Winter Olympics quarters on Saturday, an Austrian Olympic chief and investigative source said.
"The searches are ongoing in the Austrian biathlon staff's lodgings. They were made at the request of the Turin prosecutors," said the source.
The subject of the investigation is the possible presence of banned substances, he added. The secretary-general of the Austrian Olympic Committee Heinz Jungwirth told Reuters there had been a police raid on Austrian biathletes in Pragelato.
"There was a suspicion of doping and the athletes had to submit to doping tests," he said.
Sources close to the International Olympic Committee (IOC) said it would issue a statement shortly.
There have been six biathlon races so far at the 2006 Winter Games and not one Austrian medallist in the sport.
There are four more biathlon races due before the end of these Winter Olympics. The next is scheduled for Tuesday.
The Italian government, which introduced strict doping laws before it won the right to host the Turin Olympics, has refused to relax them to correspond with IOC rules which foresee only non-penal sanctions for drugs users.
Even a last-minute compromise between the IOC and the host country on who would handle the doping tests during the Games had failed to include a moratorium on launching criminal procedures against athletes found using banned substances.
That left the IOC concerned that athletes could be subjected to police raids and face prison sentences if they tested positive.