Los Angeles ? One man bit off part of another man’s finger when a health care reform demonstration turned violent.

William Rice said doctors did not reattach the bitten-off part of his left pinky after he got in the middle of a Southern California rally Wednesday night that he said was “very scary.”

“I didn’t go out to demonstrate my beliefs, I happened to be driving by and I stopped to ask people what their purpose was,” Rice, 65, said in a telephone interview Thursday. “I had no signs, I was not part of the demonstration.”

About 100 demonstrators in favor of health care reform had gathered on a Thousand Oaks street corner for an event organized by MoveOn.org. About 25 counterdemonstrators gathered across the street.

Rice declined to say Thursday which side of the debate he falls on.

Ventura County sheriff’s spokesman Eric Buschow said a confrontation erupted after the biter crossed from the MoveOn.org side of the street to the counterprotest, where Rice was standing.

A loud scuffle ensued, punches were thrown, and the tip of Rice’s finger was bitten off, Buschow said.

The biter fled before authorities arrived. He could face felony mayhem charges.

“We don’t know the identity of the man who bit the finger off,” Buschow said. “We want to contact him and get his side of the story.”

Buschow said authorities are piecing together the events from witness interviews.

There are conflicting accounts of who started the fight, Buschow said. “There’s a question about blurring the line between self-defense and who the primary aggressor was,” he said.

Rice was treated at Los Robles Hospital and Medical Center. The top joint of his pinky, including his whole fingernail, was severed, hospital spokeswoman Kris Carraway-Bowman said.

She said his treatment was covered by Medicare.

Rice said he and his attacker did not have a conversation about health care unless “you want to call him screaming in my face that I’m an idiot a conversation.”

MoveOn.org spokeswoman Ilyse Hogue said in a written statement that the incident is a “regrettable act of violence” but the group had few facts about the situation.

The group is in favor of health care reform that includes a “public option” providing government-sponsored insurance.

Scuffles and noisy protests over the proposed health care overhaul have broken out at recent town hall meetings hosted by members of Congress across the country.