Beijing(CNN) China is set to release the last known prisoner of the 1989 Tiananmen Square uprising, according to Dui Hua, a San Francisco-based human rights organization.
Miao Deshun was one of more than 1,600 people charged during the bloody crackdown on the student movement.
Dui Hua said they had obtained documents from the Beijing No. 1 Intermediate People's Court that said he would be released from Beijing's Yanqing prison, on October 15.
Miao's family stopped visiting him years ago according to Dui Hua, and there are no photos of him in the public domain.
Once he's released, Miao will have his political rights "deprived" for seven years. Those are a person's right to vote, to stand for election and to freedom of speech.
Born in China's northern Hebei province, Miao was a 24-year-old factory worker at the time of the crackdown.
He was given a suspended death sentence for arson in August 1989 for throwing a basket into a burning tank, according to Dui Hua.
Tiananmen 25 years on: The day I drove famed hunger strikers to safety
The sentence was subsequently reduced at least twice -- to life imprisonment in December 1991 and to 20 years in September 1998.
China's state-run media has said nothing about his release.
"Even 27 years on, remembering Tiananmen is considered subversive by the authorities," said William Nee, China Researcher at Amnesty International.
"The Chinese government continues to run the world's largest censorship apparatus -- in part to block the spreading of sensitive historical information like the Tiananmen crackdown -- and it continues to harshly deal with the few people who bravely attempt to commemorate and pay tribute to those who died during the period."