Other prisoners beat a blind Chinese activist who was jailed after he documented cases of forced abortions. They also held him on the ground and shaved his head, his wife said Friday.
Chen Guangcheng staged a hunger strike to protest the attack that left him with cuts on his legs and swelling around the ribs, his wife, Yuan Weijing, said in a telephone interview.
A shaved head is a defining characteristic of Chinese prison inmates and Chen - protesting his innocence - had refused to wear his hair any shorter than a crewcut, Yuan said.
"Ever since he went to jail ... he never acknowledged that he was a criminal. He said, 'I'm a Chinese citizen. I'm here, but I'm not a criminal,"' Yuan said. "He said you can give me a haircut, you can give me a crewcut, but you can't shave my head."
Chen was convicted in August 2006 on charges of instigating an attack on government offices in his village of Dongshigu in eastern China's Shandong province. Police said he was upset with workers sent to carry out poverty-relief programs.
He also was accused of organizing a group of people to disrupt traffic, allegedly delaying hundreds of vehicles for three hours, including an ambulance carrying an expectant mother to a hospital.
Human rights activists say his case is an example of official retaliation and unjust imprisonment of dissidents based on phony charges. His supporters say he is innocent and that officials fabricated the charges after he documented complaints that officials trying to enforce China's birth-control regulations had forced villagers to have late-term abortions and sterilizations.
Chen, who was blinded by a fever in infancy, told his wife when she visited Linyi Prison on Tuesday that he had been beaten three days earlier by six or seven other inmates. The men then held him down while his head was shaved, she said.
Yuan said she worried about her husband's safety. She said that as the men assaulted her husband, they told him: "Don't you know, the Communist Party is going to give us extra points (toward early release) for beating you."
The human rights group Amnesty International said it believed Chen's life was in danger.
It said Chen's beating was ordered by prison guards as punishment for filing an appeal. He needs the help of his wife or a lawyer to draft the appeal, but so far has not been able to because he is only permitted one 30-minute visit a month, the group said.
Chen refused food and water for at least 76 hours after the attack but prison officials told Yuan on Thursday that he had started eating again, she said.
They also said a medical examination found Chen to be in good health.
"They said what happened wasn't that others had beat Guangcheng, Guangcheng had hit others. When I heard this, I couldn't take it," Yuan said, her voice wavering. "I said: 'We all saw his injuries, where did they come from? Did he hit himself?"'
Jail officials told Yuan they didn't have an explanation, she said.
A man who answered the phone at Linyi Prison said he did not know anything about the case. Calls to the official in charge of the facility rang unanswered Friday afternoon.