The former executive director of Russia's anti-doping agency, Nikita Kamaev, has died, Tass news agency reports.

His death comes two months after he resigned his post at Rusada following the doping scandal which engulfed Russian athletics.

Tass quoted Rusada's former director general Ramil Khabriev as saying it appeared to have been a heart attack.

Russia was suspended from international athletics last November.

A commission of the World Anti-Doping Agency (Wada) accused Russian athletics of state-backed doping and corruption.