Police in China have arrested and charged more activists with subversion, rights groups say, as online calls Sunday urged Chinese to join anti-government rallies for the fourth week running.
Guo Weidong, 38, was charged with "inciting subversion" Friday after he posted Internet calls for protesters to attend rallies marking the "Jasmine revolution," the Information Centre for Human Rights and Democracy in China said.
Guo, a businessman in east China's Zhejiang province, was taken into police custody Thursday, the Hong Kong-based centre said in a statement.
Chinese authorities have launched a security clampdown in major cities in response to calls for protests inspired by the "Jasmine revolution" in Tunisia, which sparked a wave of unrest against authoritarian regimes in the Arab world.
Police have been deployed in force on the last three Sundays in both Beijing and Shanghai to prevent any demonstrations and block foreign media coverage of them.
No public protests have been seen, although foreign journalists were beaten at a designated rally site in Beijing two weeks ago by thugs believed to be linked to police.
As in previous weeks, posts on overseas Chinese websites and micro-blogs again urged disgruntled Chinese to "stroll and smile" in designated sites in 34 cities on Sunday, but to "take no action and avoid confrontation" with police.
According to the Chinese Human Rights Defenders (CHRD), also based in Hong Kong, Guo was the 18th activist to be arrested and charged for alleged links to inciting the protest.
At least three other activists have been charged over the past few days.
Up to 100 activists around China have been placed under house arrest, interrogated or taken into police custody without charge for their alleged links to the rallies, CHRD said earlier.
On Sunday, at Beijing's Wangfujing commercial district -- a designated rally site -- there was no massive police presence as seen on previous Sundays.
Security in Beijing, however, has been tight since the annual 10-day meeting of parliament started in early March when state press announced that some 180,000 police and 560,000 security volunteers began patrols in the capital.
In Shanghai, no major unrest was seen, but police were seen checking identification papers and urging journalists to depart from the designated rally site on People's Square.
Wary of the potential for social unrest across China, Premier Wen Jiabao pledged last month to tackle a range of hot-button public concerns including soaring inflation, runaway economic growth, and official corruption.
China's leaders have watched with worry as those and other issues touched off political convulsions in the Middle East and North Africa.