Amnesty International demanded the immediate release of Beijing housing activist Ye Guozhu on 23 July. He was due to be released on Saturday 26 July, but will now remain imprisoned until 1 October, after the end of the 2008 Olympic Games.

"Ye Guozhu is being kept in prison to prevent him from speaking out about the people, like himself, who were forcibly evicted from their homes in Beijing to make room for the Olympics," said Amnesty International.

"This is in complete contradiction of the promises China made to improve human rights before the start of the Games."

According to Ye's family, the Chaobai prison authorities telephoned them on 22 July, informing the family they should not go to the prison to receive Ye Guozhu on 26 July, the original date for his release. The prison authorities said that Beijing Xuanwu district police had taken Ye away. The Xuanwu District police later said that for the good of the family and to keep them out of trouble during the Olympic Games, the police would take care of Ye Guozhu but would not allow him to return home until sometime after 1 October 2008. The police refused to let the family meet Ye Guozhu or tell them where he is now being detained.

Ye Guozhu, considered by Amnesty International as a prisoner of conscience, was sentenced to four years' imprisonment in 2004 for his opposition to forced evictions in Beijing associated with construction for the Olympic Games.

In 2006 it emerged that Ye was tortured while in detention. Police at the Dongcheng district detention centre in Beijing reportedly suspended him from the ceiling by his arms and repeatedly beat him. He was also reportedly tortured in another prison in the second half of 2005.