More doping drama out of Russia, a week before the Under-18 World Championship.

TSN's Frank Seravalli reports that "more than half of the 30 players in Russia's (Under-18) evaluation camp tested positive for meldonium," a performance-enhancing drug recently banned by the World Anti-Doping Agency. It's the same substance that resulted in a failed drug test for Russian tennis star Maria Sharapova.

The news was first reported by AllHockey.Ru and Russian hockey writer Slava Malamud, who writes that Russia will be sending its Under-17 team to the Under-18 worlds.

The Under-18 tournament begins April 14 in Grand Folks, N.D. The Russian team was supposed to depart for the United States on Thursday.

"We'll announce the roster (Thursday)," Vladislav Tretiak, the president of the Ice Hockey Federation of Russia, said.

Rosters don't have to be officially submitted until April 13.

Meldonium is "only distributed in Baltic countries and Russia," according to The Guardian, and "increases blood flow, which improves exercise capacity in athletes."

TSN's Darren Dreger reports that Canada's Under-18 team will be tested for the drug Thursday.

Malamud appeared on local radio in Toronto on Wednesday and said meldonium is widely used in hockey in Russia.

Copyright © 2016 Score Media Ventures Inc. All rights reserved. Certain content reproduced under license.