Three Chinese activists who allegedly attempted to start a non-violent civil rights movement stood trial on Thursday, a relative told AFP, as the ruling Communist party continues a crackdown on dissent.

Tang Jingling, Wang Qingying and Yuan Xinting each face possible 15 year jail sentences for "inciting subversion of state power," their lawyers have said.

Police recommended the trio be prosecuted for having "participated in the non-violent Citizen non-cooperation Movement," according to a statement posted online by their lawyers.

Their trial began on Wednesday in the southern Chinese city of Guangzhou, Tang's wife Wang Yanfang told AFP in a brief text message.

China's ruling Communist party has for decades jailed activists seen as a threat to its rule, with dozens imprisoned since President Xi Jinping took office two years ago.

The Communist party controls the country's courts and the three men are almost certain to be found guilty and jailed.

Hong Kong media said there was a heavy state security presence outside the courthouse, adding that police detained several activists who turned out to support the trio.

The three distributed books about non-violent resistance and "wilfully incited the subversion of state power and the overthrow of the socialist system," police said in their statement to prosecutors.

They added that the activists had rented an office to study, print, and mail several books including one titled "On Strategic Nonviolent Conflict: Thinking about the Fundamentals".

The three are also accused of disseminating "From Dictatorship to Democracy," by Gene Sharp, an expert on non-violent social movements.

The books "have been confirmed to have serious political transgressions," police added in their statement.

China's state security have detained or called in for questioning more than 200 human rights lawyers and activists this month, in what analysts have called one of the biggest crackdowns on dissent in years.

Tang, 44, was himself a prominent human rights lawyer who had aided farmers attempting to take local officials accused of illegal land seizures to court.

He announced the founding of a small-scale "Non-violent Civil Disobedience Movement" in 2006, according to US-based group Human Rights in China.