Wang Ruowang, known as one of the "fathers" of political dissent in China has died in exile in the United States aged 83, a dissident group said.
According to the president of US-based Human Rights In China (HRIC), Liu Qing, Wang died on Wednesday evening local time at a hospital in New York. He was suffering from lung cancer.
Mr Wang joined the Communist Party in 1937, having spent three years in a Nationalist jail, but began falling out with party authorities over ideological differences during the 1940s.
He was eventually expelled from the party for the first time in 1957, amid an "anti-rightist" campaign.
During the Cultural Revolution, from 1966-76, Mr Wang spent four years in prison for criticising then-leader Mao Zedong, and was later forced into labour camps.
In 1979 Mr Wang was rehabilitated and allowed back into the party, but he was expelled again in 1986 for advocating Western liberal causes and supporting an early wave of protesting students.
He then backed the Tiananmen Square pro-democracy movement, crushed by the Chinese army in June 1989, leading to another jail term.
Freed in 1992, Mr Wang was finally allowed to leave China along with a number of other dissidents.
After his exile, he produced from the US a series of articles critical of Chinese authorities.
AFP