"Witnesses saw the fight and heard the attackers shout: 'Russia is for Russians!" Ruslan Koblev said.
Zaur Tutov, culture minister of Kabardino-Balkaria and a famous singer, said he had been attacked by some 15 men when he was picking his daughter from a folk dance class Saturday night.
Prosecutors said Tutov had been hospitalized with a broken cheekbone, concussion, and bruises on his face and was expected to undergo a surgery Sunday.
Moscow prosecutors, who earlier said they had no evidence of racial motivation, opened investigation, treating the incident as an act of hooliganism resulting in injuries.
"This is another attempt to qualify an ethnically motivated crime as an act of hooliganism," Koblev said, echoing public criticism of police for unwillingness to address racially motivated attacks that have plagued the country in recent years.
Sergei Marchenko, a Moscow prosecutor, said earlier that prosecutors were inquiring into police' response to the incident, acting on complaints from Kabardino-Balkaria's government, which said the police had been too slow to arrive.
