Sergei Filin, 42, spoke to investigators in a Moscow hospital, Bolshoi director Anatoly Iksanov said, adding that they also questioned his colleagues, who said the attack was likely triggered by envy, rivalry or competition for roles in Russia's most prestigious theatre.

"Investigators are questioning those who worked in the theatre, artists," said Iksanov on the snowy grounds outside the hospital, where Filin was receiving visitors.

A masked assailant threw acid in Filin's face late on Thursday night outside his house as he returned home from the theatre. Colleagues said Filin believes the attacker had been following him and called him by name before striking.

An icon of Russian culture, the Bolshoi Theatre is a magnet for tourists and has seen power struggles among dancers and directors throughout more than 200 years of history.

Since the collapse of the Soviet Union in 1991, many of those conflicts, whether driven by egos or artistic conviction, have been played out in public.

Iksanov said he and Filin discussed the theatre's future during his absence and that a temporary replacement had been chosen.

"It was Sergei's choice," he told Russia 24 television, without naming the candidate.

The chief physician at the hospital was quoted by Itar Tass as saying Filin was in bandages following surgery on Friday but was able to walk and eat.

Iksanov said medics feared for his eyesight.

"The doctors' biggest fear is the trauma (on) Sergei's eyes and in the course of two weeks, it will be understood what kind of procedures, what has to be done," he said.

"The next operation has been decided, it will happen on Tuesday or Wednesday."

Bolshoi Theatre spokeswoman Katerina Novikova said previously Filin would be transferred to a burn centre in Belgium, but government spokesman Alexei Levchenko, speaking to Interfax, dismissed those plans, saying he would stay in Russia.

"The question is not worth asking ... with (Russia's) conditions, the necessary treatment is being provided to S. Filin," said Levchenko, the spokesman for Deputy Prime Minister Olga Golodets, who has been ordered to oversee the case.

After the tightly-controlled three-decade tenure of Yuri Grigorovich ended in 1995, the Bolshoi Ballet went through five artistic directors before the appointment in March 2011 of Filin, who joined the Bolshoi's ballet troupe in 1988.

(Reporting By Thomas Grove; Editing by Jason Webb)

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