BEIJING — Chinese authorities continued to tighten controls on Internet use Friday in the face of murky calls for “jasmine rallies” to emulate the anti-government protests convulsing the Middle East and North Africa.

The professional networking site LinkedIn was blocked in China, joining sites such as Facebook, Twitter and YouTube that already were inaccessible due to government controls. LinkedIn was apparently blocked after a user began a discussion group called “Jasmine Voice.” The user asked followers to comment on the possibility of a “jasmine revolution” in China.

“I think it’s pretty clearly connected to the number of postings about the jasmine stuff,” said Jeremy Goldkorn, founder of a popular Chinese media blog and an expert on the Internet here.

Also Friday, the Chinese name of U.S. Ambassador Jon Huntsman Jr. joined the list of terms blocked from searches on popular Chinese micro-blogging sites, along with previously banned words including “Tunisia,” “Egypt” and “jasmine.” A search for Huntsman’s Chinese name on the sites turned up only the notice that the results could not be returned due to “relevant regulations and policy.”

Huntsman drew the ire of Chinese nationalists here after briefly appearing last Sunday in Wangfujing, a commercial pedestrian area of central Beijing. Organizers of the jasmine rallies, whose identities are unknown but who seem to be affiliated with an overseas organization, had asked Chinese to silently pass through the area as a peaceful form of protest against government authoritarianism. Few protesters actually appeared to show up, however, mainly due to a massive police presence in the area.

Huntsman, in sunglasses and a leather jacket, was out of his car talking to an unidentified passerby when he was caught on camera by a person who appeared to be a plainclothes policeman. That person confronted the ambassador, asking, “Do you want to see chaos in China?” Huntsman quickly left the area.

The U.S. embassy said Huntsman’s appearance at the site was “purely coincidental” because he was in the area with his family on a Sunday outing.

“We are aware that some Chinese domestic Internet sites are restricting searches of Ambassador Huntsman’s Chinese name,” said U.S. embassy spokesman Richard L. Buangan. “We urge China to respect internationally recognized fundamental freedoms, including freedom of expression, and the human rights of all Chinese citizens.”

This week in Wangfujing, workers erected a large blue construction fence in front of a McDonalds restaurant where the rally organizers had asked protesters to silently pass.

Merchants in the area said the fence went up two days ago, ostensibly because of needed sidewalk repairs — but Friday there was no sign of any construction activity. The fence, however, takes up much of the pedestrian mall area and significantly narrows the space where people can pass.

Since the popular uprising began in Tunisia in January, nervous Chinese authorities have been on guard against any attempt to replicate the protests here.

Friday’s edition of Global Times — a tabloid newspaper owned by the Communist Party’s official organ, People’s Daily — ran a lead editorial titled: “Turmoil in China is wishful thinking.”

The editorial blames “a few Western media outlets” for trying to promote unrest in China, and opines, “Anyone knowing about the Chinese society would never predict a Chinese-style ‘Jasmine Revolution.’ This society is now generally stable.”

In another sign of the unease, several Western media bureau chiefs were called into the main office of the Beijing police on Friday and warned to be mindful of the State Council’s rules governing foreign reporters conducting interviews in China.

Washington Post researcher Zhang Jie contributed to this report.