Freed after over four years' imprisonment for speaking out against mass forced abortions and sterilisations, the ordeal of one of China's famous human rights activists continues.

The blind Chen Guangchen was released Thursday from prison after serving four years and three months on the charge of 'intentional destruction of properties and inciting a mob to disrupt traffic', said Christian rights organisation China Aid.

Chen won the Magsaysay award for defending human rights and in 2006 was named by Time magazine among the world's 100 most influential people.

He was placed under house arrest in 2005 after he spoke to Time magazine about the cases of abortions forced by the state in Linyi in Shandong, eastern China.

Chen, a self-taught lawyer, exposed how local officials, in a bid to implement the 'One child' policy of China, had forced tens of thousands of people to undergo abortion and sterilisation. He also filed a class-action suit on behalf of the victimised women that, however, was rejected.

Imprisoned in 2006, Chen was reportedly brutally tortured and denied medical treatment. His wife was allowed to meet him only thrice in four years.

In an interview with Radio Free Asia after his release, Chen said the 'maltreatment' in prison was 'very serious' when he was first arrested. He also said he wanted to thank his 'friends all over the world for their concern'.

On his release Thursday, his wife and family members were not allowed to meet him at the prison to bring him home.

Now he and his family are being closely monitored by more than 20 policemen surrounding his home, China Aid said.

No one has been allowed out of the house Friday, even for shopping.

'The authorities have threatened Chen and his wife that they will throw any family member in prison at any time, if they fail to cooperate,' China Aid said in a press statement.

Chen is currently in poor health, suffering from debilitating diarrhoea and needs medical treatment.

(Sudeshna Sarkar can be contacted at sudeshna.s@ians.in)