The US State Department says an employee of the Patent and Trademark Office who made a personal visit to China has been barred from leaving the country.

A State Department spokesperson told NHK on Monday, "We are tracking this case very closely and are engaged with Chinese officials to resolve the situation as quickly as possible."

The Patent and Trademark Office is a federal agency under the US Department of Commerce.

The Washington Post has reported that the employee is a Chinese American man, who traveled to China several months ago to visit family.

The paper said the man is being prevented from leaving China after he failed to disclose on his visa application that he worked for the US government.

A female executive of major US bank Wells Fargo has also been blocked from leaving China.

A Chinese Foreign Ministry spokesperson said on Monday that the woman "is involved in a criminal case currently being handled by Chinese law-enforcement authorities and is subject to exit restrictions."

The spokesperson added that "anyone, Chinese and foreigners alike, should abide by Chinese laws in China."

Reuters news agency said Wells Fargo has suspended all employee travel to China in response to the incident. (NHK World)