A Chinese paramilitary policeman closes off a road leading to embassies in the Sanlitun district of Beijing on Thursday.Ng Han Guan / AP

The U.S., British, and other embassies in Beijing warned their citizens to be vigilant in the popular Sanlitun neighborhood on or around Christmas Day.

“The U.S. Embassy has received information of possible threats against Westerners in the Sanlitun area of Beijing, on or around Christmas Day,” the U.S. Embassy said in a statement issued on Thursday. “U.S. citizens are urged to exercise heightened vigilance. The U.S. Embassy has issued the same guidance to U.S. government personnel.”

Neither the nature of the threat nor its origin was specified.

The British Embassy issued a near-identical warning. Warnings were also issued by the embassies of Australia and France.

Sanlitun is an area in Beijing’s Chaoyang district. Popular with tourists, it has several bars and restaurants. It is also home to several foreign embassies, though the U.S. Embassy is located elsewhere.

Xinhua, the state-run Chinese news agency, reported that Beijing police had initiated on Thursday a yellow security alert for malls and supermarkets during the Christmas season. Here’s more:

A yellow alert is the second mildest under the four-coded alert system, which goes from green, yellow, orange to red in order of severity. It means 60 percent of the security personnel in those shopping malls and supermarkets should carry out security checks on suspected personnel, materials and vehicles, according to a government security prevention regulation.

All trash bins in public areas should be checked every 30 minutes, according to the regulation.

The BBC adds armed police were deployed Thursday outside shopping malls in Sanlitun.

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