An associate of imprisoned Russian opposition leader Alexei Navalny has been imprisoned on extremism charges as part of the Kremlin’s ongoing crackdown on political activists.

TORONTO (AP) — Toronto Maple Leafs prospect Rodion Amirov has been diagnosed with a brain tumor.

Maple Leafs general manager Kyle Dubas said Wednesday in a statement that the 20-year-old Russian winger is undergoing treatment in Germany and will not return for the remainder of the season.