Police Commissioner Raymond W. Kelly described the incident as a bias case based on statements by Mr. Nimmons and at least two witnesses. Mr. Kelly said the homeless man had been rummaging for discarded clothing in a walkway behind the Lubavitchers' headquarters at 770 Eastern Parkway around midnight when he was confronted by a Hasidic man. Beat With a Stick

The man asked Mr. Nimmons what he was doing and then said he was going to hold him for the police. Within a few minutes, as many as 20 Hasidic men arrived and tried to hold Mr. Nimmons. But when the homeless man resisted, Mr. Kelly said, the group beat him with a wooden stick and a radio while yelling racial slurs.

"It's being deemed a bias case because racial slurs were used," the Commissioner said at a news conference at Police Headquarters. "We're not certain at this juncture what motivated the attack."

But Rabbi Joseph Spielman, a spokesman for the Crown Heights Jewish Community Council, said Mr. Nimmons was not a victim, but a known burglar who had broken into the "colel," or post-graduate rabbinical school, on Union Street that night. A neighbor had seen the break-in and alerted a group of young men, he said. The group confronted Mr. Nimmons as he left through a door and tried to hold him for a citizens' arrest, but Mr. Nimmons, he said, had a knife and resisted violently.

"They hit him to try to subdue him," Rabbi Spielman said. The rabbi also said no racial words had been used and there had been "no racial overtones" to the incident.