Guo Quan, a professor at Nanjing Normal University in eastern China and frequent government critic, was taken into police custody on Thursday, his wife Li Jing said by phone.

Guo formed the China People's Livelihood Party in 2004 - renaming it the China New People's Party late last year - to protect the rights of 'workers, farmers, businessmen, students, and urban residents,' according to Guo's blog, which is blocked in China.

'Police gave his mother an official notice saying Guo is suspected of subverting state power,' Ms Li said.

'Subversion of state power' is a vague charge that critics of China's government say is used by the ruling Communist Party to silence dissenters.

The party retains a steely grip on all political activity in China.

It allows eight other parties to exist, but they remain subservient to the interests of the ruling party.

'It is suspected that Guo might have been detained for organising the China Xinmin Party (New People's Party),' China Human Rights Defenders, a network of Chinese and overseas rights activists, said in an emailed statement.

In a recent blog entry, Guo called China's eight other legal parties 'flowers in a vase' meant to give the appearance of democracy in China.

The group also said the arrest could be linked to articles published online by Guo that criticised the Nanjing city government, particularly for its construction of a chemical plant.

Guo had previously been stripped of his teaching duties over his activism and his been held in detention before, according to his blog.

Despite promises to respect human rights for the Olympics, China launched a crackdown on government critics this year during the lead-up to the Beijing Games, which were held in Aug.

Several prominent dissidents have said recently they feared the crackdown had set the stage for a lasting period of even tighter controls.

Guo's blog claims the China New People's Party has 10 million members and branches in all provinces of the country. -- AFP