BEIJING — The head of the IOC's medical commission said seven Russian female track and field athletes, accused of tampering with their urine samples, appeared to be involved in a case of "systematic doping."

Seven Russian women were provisionally suspended last week by the IAAF in the doping scandal. They included Yelena Soboleva, a world record-holder and world champion middle-distance runner who was favored to win both the 800 and 1,500 meters at the Beijing Olympics.

"I think it is just frustrating to find that such type of cheating — planned cheating — is still going on," Arne Ljungqvist said Tuesday, the chairman of the International Olympic Committee's medical commission. "That's very disappointing to find."

Ljungqvist called on the Russian track and field federation to investigate the case.

"Obviously the data are convincing," Ljungqvist said. "The DNA analysis are 100 percent. So if the urine does not belong to the athlete ... then they certainly have a case to answer. It's a sad story."

A former vice president and medical chief of the IAAF, Ljungqvist said under new doping rules the athletes could be banned for four years instead of two. The four-year ban for systematic doping is a recent change to the World Anti-Doping code.