Four Russian judo wrestlers have become the latest athletes to test positive for the banned substance meldonium, Russian media report.
The TASS news agency identified the four judokas as 2012 world champion Mikhail Pulyaev, Denis Yartsev, Natalia Kondratiyeva, and Yekaterina Valkova.
Russia's judo federation refused to comment.
Some 30 other Russians across all sports have tested positive for meldonium, which was banned on January 1, with more than 120 cases worldwide.
The meldonium scandal began in March when Russian tennis star Maria Sharapova announced that she had tested positive for the drug at the Australian Open in January.
The five-time grand-slam champion has said she had been taking meldonium for medical reasons.
A string of high-profile Russian athletes -- including Olympic swimmer Yulia Yefimova and speed skaters Semyon Yelistratov and Pavel Kulizhnikov -- have since admitted to testing positive for meldonium.