MOSCOW, March 19 - RAPSI, Maria Petrova. The attorney of Andrei Lipatov, who has been accused of involvement in the January 17 acid attack on the Bolshoi Theatre's artistic director Sergei Filin, has refused to sign a non-disclosure agreement, the lawyer Sergei Zhorin himself told RAPSI on Tuesday.

Sergei Zhorin explained his refusal by claiming that the request was invalid, and that the case does not contain state or private confidential information. The investigators appear to be trying to ensure that only specific information that reflects the official position reaches the media, he said.

Zhorin has also requested a repeat expert evaluation of the liquid that the attackers threw into Sergei Filin's face. He said the investigators have not established the solution's concentration and that "it might not have been acid at all."

"If experts report that the liquid was not concentrated enough to do serious harm, my client should be released with travel restrictions, under the moderate injury clause," he added.

Filin suffered third-degree burns to his face and eyes on January 17 when unknown assailants attacked him with what is believed to have been concentrated acid.

Lead soloist of Bolshoi Theater Pavel Dmitrichenko stands accused of having organized the attack. He and two others - the alleged actual attacker Yury Zarutsky and Andrei Lipatov, who drove him to the crime scene - have been detained in connection with the case. If convicted, the assailants face up to eight years in jail for willfully inflicting damage on the health of another individual.

Over 300 members of the Bolshoi Ballet company have signed a letter in defense of Dmitrichenko.

Filin, 42, joined the Bolshoi as a dancer in 1988 after graduating from the Moscow School of Choreography. He has also been invited on several occasions to dance with the English, Hungarian and Japanese national ballets, as well as many other theaters. He ended his dancing career in 2008. In March 2011, he was appointed artistic director of the Bolshoi Theater amid fierce rivalry for the position.