Hamburg - The International Biathlon Union (IBU) on Thursday provisinally suspended the athletes who submitted positive doping tests at the World Cup opener in December.

The announcement came little more than a week ahead of the world championships in Pyeongchang, South Korea, from which these - allegedly three Russian - athletes are now barred even if the case is not solved by then.

The IBU said that "the substance found in the positive a-samples of the athletes are non-specified substances of the WADA Prohibited List.

"The suspension shall take immediate effect. A provisional suspension means that the athletes are barred temporarily from participating in any IBU competition."

The IBU has neither named the athletes not their nationality or the substance as the case is pending and the athletes in question have asked for examination of the b-sample which according to the IBU will take place "as soon as possible."

Russian officials have acknowledged that the cases involve their team.

Russian daily Komsomolskaya Pravda on Wednesday named the three athletes, saying that World Cup leader and world champion Eketarina Iourieva, three-time world champion Albina Akhatova as well as two-time relay world champion Dmitri Yaroshenko were the suspects.

The paper cited unofficial sources in its report.

Yaroshenko has protested his innocence, telling the life. ru website on Thursday that he never doped in his life.

The athletes were allegedly caught blood doping with a new substance (not EPO or its third generation known as CERA) in target tests at the World Cup opener in Ostersund, Sweden, Russian media said. (dpa)