Moscow: Russia on Monday announced four doping failures for meldonium in athletics as the country battles to be reinstated in time for the Rio de Janeiro Olympics.
These are the first known cases of the banned drug in Russian athletics in a potential blow to efforts to overturn an International Association of Athletics Federations (IAAF) suspension from international competition because of doping scandals.
The athletics federation did not name the four athletes who tested positive. It was unclear whether sprinter Nadezhda Kotlyarova, who admitted to taking the banned drug on Sunday, was among them.
An unnamed source told TASS news agency however that the four athletes are Kotlyarova, long-distance runners Andrei Minzhulin and Gulshat Fazletdinova, and steeplechaser Olga Vovk. All are said to have tested positive for the drug at the Russian indoor championships last month.
The federation said in a statement it was conducting a "thorough investigation" into the cases and reiterated it had repeatedly warned athletes and trainers that the World Anti-Doping Agency was banning meldonium from January 1.
The drug is widely used for heart conditions and diabetes. But it also helps recovery from physical exertion so could help athletes.
A number of high-profile Russian athletes, including tennis star Maria Sharapova, short-track speed skater Semyon Yelistratov and swimmer Yulia Yefimova, have tested positive for meldonium.
Sports Minister Vitaly Mutko said Monday the meldonium scandal was not affecting Russian athletes' preparations for the Rio Olympics which start August 5.
Russia was suspended by the IAAF for other doping failures said to be "state sponsored". The IAAF will only decide in May whether Russian authorities have made enough efforts to return to international competition.
"All those who are training for the Olympics are being monitored," Mutko told TASS. "The issue of meldonium is a separate issue."
President Vladimir Putin last week blamed Russia's sports officials for failing to warn athletes that meldonium was being banned by WADA.
WADA says that more than 100 suspected positive tests have been recorded since January 1.
The agency moved meldonium from its "monitored" to "prohibited" list "because of evidence of its use by athletes with the intention of enhancing performance."