An octogenarian Chinese writer who has spent more than two decades in labour camps will be put on trial Wednesday, his lawyer said, as part of Beijing's crackdown on critics of the Communist Party.

Tie Liu, 81, whose real name is Huang Zerong, will be tried in the southwestern city of Chengdu, his lawyer Liu Xiaoyuan told AFP.

The writer was taken away by Beijing police in September for "picking quarrels and provoking trouble" -- an allegation frequently used to silence those who challenge the ruling party -- and was formally charged in October with "running an illegal business".

His assistant Huang Jing will also stand trial on Wednesday, Liu said.

The proceedings are being held in Tie's hometown, some 1,800 kilometres (1,100 miles) away from his residence in the capital, in what appears to be an attempt to minimise public attention on the case.

They are also taking place immediately after China's week-long Lunar New Year holiday, during which most business in the country comes to a standstill.

The authorities "don't want a lot of attention on this case before a verdict is announced", Liu told AFP by phone. "They want it to be low-key."

Tie -- who turned 81 last May -- has long been a thorn in the side of the Communist Party.

As a young journalist critical of Mao Zedong, founding father of the People's Republic, he spent more than 20 years in labour camps before being rehabilitated in 1980.

More than 10 police officers raided Tie's house in September and took away computers and books.

Tie's wife has said she believes her husband has been targeted because of a critical essay he wrote about top Communist Party propaganda official Liu Yunshan.

International groups, including the PEN American Centre, have called for Tie's immediate release.

Tie's detention comes amid a broad crackdown on dissent in the past two years since Chinese President Xi Jinping rose to power, with dozens of journalists, human rights activists, lawyers and others rounded up.