Boney M frontman Bobby Farrell died of heart disease, Russian investigators said on Wednesday, almost a week after the singer was found dead in his hotel room in St. Petersburg.

"It was not a suspicious death. Heart disease was the cause," Sergei Kapitanov, representative of St. Petersburg's branch of Russia's investigative committee, said by telephone.

Farrell, 61, was famous for dancing and lip synching for the disco band Boney M, which rose to prominence in Europe, the United States and the Soviet Union with songs like "Rivers of Babylon" and "Rasputin."

He was found dead on December 30 after Boney M performed in the Russian imperial capital -- a city where the band rose to stardom in the Soviet era.