The U.S. State Department updated its Level 2 travel warning for China, urging Americans to "exercise increased caution" when traveling in China because of "arbitrary enforcement of local laws" and "special restrictions on dual U.S.-Chinese nationals."

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Chinese authorities have used "exit bans" to prevent U.S. citizens from leaving the country, State Department officials said in the new advisory, "sometimes keeping Americans in China for years."

The updated warning said China uses exit bans:

  • to compel U.S. citizens to participate in Chinese government investigations,
  • to lure individuals back to China from abroad, and
  • to aid Chinese authorities in resolving civil disputes in favor of Chinese parties.

Many times, U.S. citizens only become aware of Chinese exit bans when they try to leave, and generally they are not provided a time frame on how long the ban will last. State Department officials also said that those detained under exit bans have been harassed or threatened.

Often those detained are not provided access to embassy or consular services and could be subjected to "prolonged interrogations and extended detentions," officials said.

Sending private electronic messages can also get an American “detained and/or deported.”

Tensions between China and the U.S. have been ratcheting up over the past year as the Trump administration imposed stiff tariffs on Chinese goods and the Chinese retaliated on U.S. farmers.

The arrest of a high-ranking Huawei official in Canada last month at the request of Trump officials has also prompted the Chinese to retaliate against Canada and possibly Americans in the future.

The State Department offers tips on its website for Americans planning a visit to China or North Korea.