A Chinese democracy activist has been sentenced to 10 years in prison for advocating government change in online articles.

The trial came amid a crackdown on activism in China that may reflect government anxiety about unrest inspired by uprisings in the Middle East and North Africa. Dozens of well-known Chinese lawyers and activists have vanished, been interrogated, held under house arrest or criminally detained for subversion.

Activist Liu Xianbin, who has previously spent a decade in prison, was found guilty of inciting subversion of state power by the Suining intermediate people's court in Sichuan province after a trial that lasted a few hours, his wife, Chen Mingxian, said.

Chinese law says inciting subversion carries a penalty of up to five years in prison, but a court can impose a longer sentence if the offence is deemed particularly grave.

Chen said she and Liu's elder brother had been allowed to attend the trial. She said her husband was calm and composed and looked relatively well, but that the judge frequently interrupted Liu and their lawyer's attempts to present a defence.

"The 10-year sentence to me, because we've already been through 10 years … is a repeat of the painful process, one in which I can only watch and wait anxiously," said Chen, who is a schoolteacher. The couple have a 13-year-old daughter.

China's government routinely uses the subversion charge to jail activists it considers troublemakers. It is not the first time Liu has been accused of it.

An indictment advice issued by the Suining public security bureau points to articles Liu wrote between April 2009 and February last year that were posted on overseas Chinese pro-democracy websites.

Liu was the author of articles that "libelled" the Communist party's leadership as "autocratic rule" and "on many occasions incited others to subvert the country's state power and socialist system", the police notice said, according to Chinese Human Rights Defenders, a China-based rights group.

In the articles, Liu allegedly also urged the Chinese to "create a strong opposition organisation" and advocated large street protests, among other things, the advice said.

"Liu's harsh sentence is part of the Chinese government's growing intolerance towards human rights activism, as reflected in the continued and widespread crackdown on activists following the online call for a 'jasmine revolution,'" said the group's research co-ordinator, Wang Songlian.

Activists in Sichuan province and elsewhere reported being taken away by police to prevent them from attending Liu's trial while others were warned against trying to go, Wang said.

Liu was a founding member of the China Democracy party and was convicted in 1999 of subversion of state power and sentenced to 13 years in prison. He was released in November 2008.

After his release, Liu continued to be involved in several high-profile human rights activities, his wife said.

He was a signatory to the Charter 08 manifesto, which called for an end to single-party rule and advocated democratic political reforms. Chinese authorities have harassed supporters of Charter 08, and co-author Liu Xiaobo was sentenced in December 2009 to 11 years in prison for incitement to subvert state power.

Liu Xiaobo was awarded the Nobel peace prize last year for his democracy activism, an honour that China condemned. Liu Xiaobo and Liu Xianbin are not related.