US warns Americans about exit bans and 'unjust' detention in popular destination

The State Department recently updated its Level 2 "Exercise Increased Caution" advisory for mainland China, warning Americans about the arbitrary enforcement of local laws, exit bans and "the risk of unjust arrest or detention."

U.S. citizens could be questioned or detained without being told what crime they are accused of - and without being given access to U.S. consular services, according to the advisory.

"U.S. citizens in China may also face interrogations and detention without fair and transparent treatment under the law," the State Department warns.

The advisory notes that business people, academics and journalists are among those who have faced questioning, detention or expulsion for alleged violations of China's national security laws.

"U.S. citizens might only become aware of an exit ban when they attempt to depart China," the advisory states.

The State Department said the restrictions have been used to pressure people to participate in investigations, resolve civil disputes and compel relatives or associates to return to China.

Officials are also warning Americans to be careful about what they say and share electronically while traveling.

Authorities have detained people over messages sent while they were outside China, according to the advisory.

"Keep a low profile," the State Department advises.

Americans are advised to exercise increased caution in Hong Kong due to the arbitrary enforcement of local laws. 

Macau carries a higher Level 3 "Reconsider Travel" advisory due to similar concerns and the U.S. government's limited ability to provide emergency consular services there.

Fox News Digital reached out to the State Department for comment and further information.