This article originally appeared on BusinessInsider.com.
The US State Department has issued a travel advisory urging Americans to "exercise increased caution" when traveling to the People's Republic of China.
The State Department's elevated travel advisory is out of concern that China may arbitrarily enforce local laws and detain US citizens without cause.
The advisory also indicates that US-Chinese citizens or Americans of Chinese heritage are especially vulnerable to "additional scrutiny and harassment."
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"Chinese authorities have asserted broad authority to prohibit US citizens from leaving China by using 'exit bans,' sometimes keeping US citizens in China for years," the State Department said in its advisory.
According to the advisory, China tends to use these exit bans in a coercive manner to "compel US 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."
In addition, the State Department warned that Americans find out about these exit bans only when they try to leave China, and they aren't notified how long the ban will last.
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The advisory also said that Americans affected by exit bans have been "harassed and threatened" by authorities.
"US citizens may be detained without access to US consular services or information about their alleged crime," the State Department said. "US citizens may be subjected to prolonged interrogations and extended detention for reasons related to "state security."
"Security personnel may detain and/or deport US citizens for sending private electronic messages critical of the Chinese government," the agency added.
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The new China travel advisory is a level-two advisory, which urges increased caution. A level-one advisory suggests travelers "exercise normal precautions," while a level-three advisory urges Americans to "reconsider travel." A level-four advisory recommends that Americans avoid traveling to a particular country.
Other countries or regions with a level-two advisory include Algeria, Antarctica, Belgium, France, Germany, Denmark, Myanmar, and the United Kingdom.