The artistic director of Russia's Bolshoi Theatre is being treated in a Moscow hospital for severe burns to his face after a masked man threw acid in his face, police say.

Sergei Filin, an award-winning ballet star, was attacked while walking home in central Moscow on Thursday. Doctors are now fighting to save his eyesight.

A Bolshoi spokesman said Mr Filin, 42, had suffered months of threats.

Steve Rosenberg reports from Moscow.