China has issued a travel alert to the US warning its visitors had been subjected to interrogations and harassment by law enforcement agencies.
The warning urges Chinese citizens and Chinese-funded bodies in the US to step up their safety awareness and preventative measures and respond "appropriately and actively".
It was issued by the foreign ministry, as well as the Chinese embassy and consulates in the US.
China's ministry of culture and tourism issued its own travel alert for the US, citing crime rates including shootings, robberies and theft in the country.
Chinese students abroad have also been told to assess the risks involved given tightened visa restrictions.
The announcements come amid an increasingly bitter trade dispute between Beijing and Washington and tougher immigration enforcement by the Trump administration.
Commenting on the warning issued to students, foreign ministry spokesman Geng Shuang said: "For some time, the US has politicised normal China-US educational exchanges using the China threat and Chinese infiltration as excuses."