An outspoken member of the Falungong group, which is banned in China, was severely beaten in a Chinese prison and has died in hospital, according to the Falungong and a right's group.
Liu Chengjun, sentenced to 19 years in March 2002 for his involvement in illegal Falungong television broadcasts, died Friday in Changchun city, the capital of Jilin province, the group said in a statement from its New York office.
Jilin prison and hospital officials told AFP they were unaware of Liu's existence and denied that any prisoner had recently died from ill treatment.
However, Frank Lu, director of the Hong Kong-based Information Center for Human Rights and Democracy, said that Liu's death was being covered up and local officials had been told not to reveal any details surrounding it.
"I called government offices and one official, who refused to be named, confirmed the death of Liu Chengjun but refused to give detailed information," Lu told AFP.
"He said if he revealed the relevant information, his boss would punish him."
According to Falungong, Liu was repeatedly beaten and tortured during his incarceration.
"Eyewitnesses who saw Liu in October 2003 said he was incapacitated and 'hard to recognize' from the torture," the statement said.
"Despite an October 24 diagnosis of 'acute kidney failure, cardiac arrhythmia, critical condition,' repeated attempts by Lius family to secure his medical parole were denied by Chinese authorities," it said.
Liu was arrested for a series of illegal Falungong broadcasts in early 2002 which interrupted television signals of state-run broadcasters and were beamed into the homes of ordinary Chinese in Jilin and other provinces.
Since a 10,000-strong protest by Falungong supporters around the Communist Party headquarters in Beijing in April 1999, the government has viewed the Buddhist and Confucian-inspired group as the biggest threat to social stability since the 1989 Tiananmen democracy protests.
It has since banned the group as an "evil cult".
Falungong claims more than 1,600 members have been tortured or beaten to death in China since a crackdown was ordered four years ago.