BEIJING - Police in the eastern Chinese province of Shandong have busted a group it said organised mass protests in an attempt to sway court cases and influence sentences, the state-run Xinhua news agency reported.

The group paid a "relatively regular" band of people to stage protests, ostensibly about protecting the rights of petitioners and lawyers working on their behalf, Xinhua said late on Sunday.

It named two of the people police detained as Zhai Yanmin, 54, who paid people to stage the protests, and lawyer Liu Jianjun, who hoped to influence judges trying his cases with the protests, the report said.

"The group was close-knit, with specific assignments for its members, and their activities were seen in heated cases across the country," Xinhua said, in a report that was also posted on the Ministry of Public Security's website.

The protesters held up banners and signs, shouted slogans and "hyped up" what was happening on Chinese and overseas websites, it added.

Tens of thousands of "mass incidents" - the usual euphemism for protests - occur each year in China, triggered by corruption, pollution, illegal land grabs and other grievances, unnerving the stability-obsessed ruling Communist Party.

Many people try to use "petitions" to bypass the legal system and directly bring complaints to the attention of government officials, in a system that dates back to imperial times, though some cases do end up in court.

Few cases ever get resolved though, and petitioners can stage noisy protests out of frustration.

Despite international criticism, petitioners are often forced home or held in "black jails", unlawful secret detention facilities where detainees can be subjected to beatings, sleep and food deprivation, and psychological abuse.

China has made a series of efforts to reform the system by cracking down on illegal imprisonment of petitioners and pushing for the process to go online. The government does not formally acknowledge that black prisons exist.

REUTERS