Turin, Italy ? The Austrians’ drug tests were negative. The doping probe is just beginning.

Austria’s biathlon and cross-country teams may have thought they were off the hook when all 10 doping samples from last weekend’s late-night raids came back Friday showing no evidence of banned substances.

But the International Olympic Committee made clear the case is far from closed, saying it will press ahead with a far-reaching probe based on evidence seized by police under Italy’s strict anti-doping laws.

The IOC said the test results on the six cross-country skiers and four biathletes were “only one element in what is undoubtedly an affair which goes far wider.”

“The IOC takes this affair very seriously and is determined to do everything in its power to bring full clarity to what has happened in the past days,” spokeswoman Giselle Davies said. “We must look at the bigger picture.”

Austrian ski federation chief Peter Schroecksnadel said Friday night that the police only found a machine to test blood sugar levels and some heart pills, both of which belong to the driver for the cross-country team. Authorities have said they seized blood transfusion equipment, syringes and other materials during the raids.

The IOC sent a letter Friday to Raffaele Guariniello, Italy’s top anti-doping prosecutor, asking him to pass on the information gathered in the probe. Once the IOC receives that evidence, it will begin disciplinary hearings into the Austrian case, a process that could stretch long after the Turin Games.

Under the IOC investigation, athletes could be disqualified retroactively and have their Olympic results annulled. Austrian team officials and coaches also could be sanctioned.

“A positive doping test does not constitute the sole basis for a doping violation,” IOC medical chief Arne Ljungqvist said. “There are other types of anti-doping rule violations, such as the mere possession of doping substances. We don’t know yet whether these athletes or coaches have been in possession. That is for the Italian authorities to inform us about.”

Markus Gandler, head of Austria's biathlon and cross-country team, right, confers with Jo Schmid, spokesman of Austria's Skiing Federation during a press conference in Sestriere, northern Italy, Friday, Feb. 24, 2006. Gandler made a statement concerning last week's anti-doping raid on the Austrian biathlon and cross-country teams, the first raid on Olympic athletes involving police.

In addition, the IOC is doing follow-up blood tests on the athletes.

“We wish to avoid the image of conducting some sort of witch hunt here, but we have reason to follow up a certain number of cases,” Ljungqvist said.

World Anti-Doping Agency chief Dick Pound, speaking before the test results were announced, said negative findings wouldn’t mean much because anti-doping officials can sanction athletes without positive tests – as occurred in the BALCO steroid scandal.

The IOC targeted the Austrians for unannounced tests last Saturday – at the same time that police raided the team’s lodgings in Pragelato and San Sicario and seized what they described as blood equipment, syringes and other materials.

The test results had been delayed for several days as the urine samples underwent detailed analysis at the official IOC doping control laboratory. Officials said the testing took longer than usual because some of the samples may have been diluted as a result of athletes consuming large quantities of water during the raids.

Only urine samples were taken from the athletes. Ljungqvist said it would have been unfair to draw blood samples for detecting blood transfusions, since some of the athletes were due to compete the following day. However, some of the athletes since have been subjected to blood controls, and others will be after the games.