WASHINGTON: The US Commerce Department placed export restrictions on several Chinese companies on Thursday for several national security reasons including what Washington says is their roles in the oppression of China’s Uyghurs or for helping Beijing’s military.

A senior administration official said the Commerce Department and Treasury Departments would announce a series of actions on Thursday targeting Chinese companies that Washington says use biotechnology and surveillance to abuse human rights.

Citing their role in the Chinese government’s alleged oppression of ethnic Uyghurs, the official said the Commerce Department will add China’s Academy of Military Medical Sciences and its 11 research institutes to its list of companies and institutions, restricting access to exports.

The U.S. move on Thursday followed a U.S. investment ban that was placed on Chinese facial recognition company SenseTime, and could worsen already rocky relations between Beijing and Washington.

“These actions come in the broader context of the administration’s efforts to address the misuse of technology to surveil, and in many cases, as with the PRC, to exercise large scale repressive social control,” the senior official told reporters, referring to the People’s Republic of China.

U.N. experts and rights groups estimate more than a million people, mainly Uyghurs and members of other Muslim minorities, have been detained in recent years in a vast system of camps in China’s far-west region of Xinjiang.

China denies abuses in Xinjiang.