Updated

A blind Chinese activist under house arrest was beaten into unconsciousness by local authorities and denied medical care, his wife said in a handwritten letter that was smuggled out of the couple's tightly guarded home.

Chen Guangcheng and his wife have been kept under an unofficial house arrest in their village in eastern China since he was released from prison last fall, and reporters trying to visit them have been kept away by men who patrol the village.

"Soft detention" is a common intimidation tactic against Chinese activists, and some house arrests have lasted years.

A group of 70 to 80 men led by a local Communist Party official stormed the couple's home in Shandong province's Shuanghou village on Feb. 18 and beat them for two hours, Chen's wife, Yuan Weijing, wrote. Her letter was posted Thursday on the website of the U.S.-based China Aid Association, a Christian rights group.

Chen passed out from the beating and Yuan may have suffered a broken rib and brow bone, she wrote.

Calls to the Shuanghou government and Communist Party offices rang unanswered Friday.

Yuan said local authorities have since put metal sheets over the couple's windows, confiscated their computers, DVD players, cameras, flashlights, books, papers and other belongings, and installed two surveillance cameras outside their home.

The couple's 5-year-old daughter has also been barred from leaving the home since Feb. 24, and Chen's mother is constantly followed by three men, even when working in the fields, Yuan wrote.

During another raid of their home on March 8, Shuanghou's vice Communist Party secretary, Zhang Jian, punched Yuan in the head after she complained about authorities taking the family's property, she wrote.

China Aid founder Bob Fu told The Associated Press on Friday that "a chain of carriers" helped to get the undated letter out of the village and into the hands of activists in China and abroad. The Associated Press couldn't immediately verify its authenticity.

Chen, a self-taught lawyer who was blinded by a fever in infancy, angered authorities after documenting forced late-term abortions and sterilizations and other abuses in his rural community. He was sentenced for instigating an attack on government offices and organizing a group of people to disrupt traffic, charges his supporters say were fabricated.

The alleged Feb. 18 beating came nine days after China Aid released a video of Chen describing his house arrest. That footage was the first word from Chen since his release in September.

"I have come out of a small jail and walked into a bigger jail," Chen said in the video.