MOSCOW: The artistic director of the Bolshoi Theater's ballet troupe was attacked with acid in Moscow and his eyesight is threatened, the theater said Friday.

Sergei Filin, a 42-year-old former ballet star, was approached Thursday night by an unknown man who splashed acid on his face as he got out of his car outside his home in central Moscow, Russian television reported.

Bolshoi spokeswoman Katerina Novikova, who visited Filin at the hospital Thursday night, told The Associated Press that his condition is stable but his eyesight is threatened.

Filin was appointed artistic director of the Bolshoi's ballet company in March 2011. He danced for the Bolshoi on and off from 1988 to 2004 when his sustained a severe injury onstage.

The theater's director general Anatoly Iksanov told Russia's Channel One that he believes the attacked is linked to Filin's work.

"He was a man of principle and never compromised," Iksanov said. "If he believed that this or that dancer was not ready or was unable perform this or that part, he would turn them down."

Several stars at the Bolshoi including Nikolai Tsiskaridze, one of its most celebrated dancers, have complained about what they call Filin's unfair treatment of dancers at the Bolshoi.