China has used its extensive system of Internet censorship, filters, and blocks to limit searches for the name of U.S. ambassador to Beijing and presidential hopeful Jon Huntsman, after he was seen in the vicinity of a pro-democracy event.
Huntsman's name did not yield any search results on the Chinese search engine Sina on Friday, although some results were returned on smaller search engines.
The blocks come amid growing online calls for a "Jasmine Revolution" inspired by the wave of popular uprisings sweeping the Middle East in recent weeks.
Activists say they have been subjected in recent weeks to a harsh crackdown on their activities and heightened surveillance by state security police.
Huntsman, who is tipped as a U.S. presidential candidate and has sparred with China on human rights, was spotted in a crowd near Beijing's Wangfujing shopping street last Sunday, the location of one of the proposed "Jasmine" rallies.
He is shown on a video later posted to the video-sharing site YouTube talking to a passerby.
Huntsman received a boost to his chances of running for the Republican presidential nomination this week with the launch of a fund-raising effort by his supporters.
China frequently uses high-tech filters to delete "sensitive" keywords from search engines.
Banned keywords added to the list of Sina's microblogging service recently have included Huntsman's Chinese name, "Egypt," "Jasmine" and "Hillary Clinton," who recently gave a speech vowing to support online activists and fight Internet censorship globally.
Around 125 million Chinese netizens use microblogs to pass on information online. The authorities have singled out microblogs as a potential tool for activists wishing to mobilize large numbers of people to protest against Communist Party rule.
The "Jasmine" rally organizers said they wish to protest widespread official corruption and put pressure on the government to accept the "supervision of the people."
But they said they do not aim to overthrow the current government.
Searches for Huntsman and Clinton were still accessible on the popular chatroom service QQ on Friday.
U.S. Embassy posts promoting Secretary of State Hillary Clinton's speech on Internet freedom were deleted from Chinese microblogging services last week.
Popular social media sites Twitter and Facebook are currently blocked in China, and the circumvention tools used by some netizens have become compromised in recent days, activists have said.
Access to the professional networking site LinkedIn was also disrupted briefly in China after users posted messages calling for more "Jasmine" gatherings every Sunday in China.
LinkedIn user Jasmine Z set up a discussion group on Feb. 23 titled “Jasmine Voice,” to post opinions on the pro-democracy protests currently spreading through the Middle East.
“After years of independent thinking, I am becoming a critical dissident dying for democracy, freedom, and justice in my homeland,” Jasmine Z wrote in the first of three posts.
A second post said China’s Communist Party members fail to “realize the crisis of the autocratic one-party system” and a third post referred to the party as “a power and elite club.”
The rights group Chinese Human Rights Defenders said on Friday that China has launched its most severe crackdown on dissidents in recent years in response to the Jasmine protests.
LinkedIn told the Bloomberg financial news service that the disruption of its service appeared to be part of a broader online crackdown, and that it would continue to monitor the situation.
Reported by Ding Xiao for RFA's Mandarin service. Written in English by Luisetta Mudie.