A leading Chinese dissident has claimed he is being held under virtual house arrest after being released from prison.

Blind activist Chen Guangcheng, who has campaigned against forced abortions and land grabs, released a video claiming he is under constant surveillance.

In the video, obtained by US-based group ChinaAid, Chen and his wife Yuan Weijing detailed the harrassment they say they have suffered since his release last September.

Yuan said: "They are very brutal. They know that Chen Guangcheng is suffering from diarrhoea at the moment but they keep us stranded at home and they won't let Chen see the doctor.

"They also don't allow us to go out to buy food. This is not only illegal but immoral. To be honest, they leave us no space left to survive."

Chen, who was jailed for four years after being convicted of damaging property and disrupting traffic in a protest, said his living conditions would not discourage him from speaking his mind.

He said: "What we need to do now through our protest is combat the fear and reveal that a series of their wicked actions and dealings are illegitimate, illegal, in violation of international treaties, inhuman and immoral."

The video, which shows men peering over the top of a fence into Chen's village home, underscores the effort the ruling Communist Party makes to monitor and restrict dissidents, even after their formal release from prison.

Chen emerged from a village in eastern Shandong province, where he overcame blindness from early childhood to school himself in law and advise residents complaining about land grabs and other official abuses.

He attracted widespread attention in 2005 by accusing officials in Shandong of enforcing late-term abortions in a drive to enforce Chinese rules that restrict most couples to one child in cities and two children in the countryside.