The US Commerce Department said on Monday it was putting 28 Chinese public security bureaus and companies – including video surveillance company Hikvision – on a US trade blacklist over Beijing’s treatment of Uighur Muslims and other predominantly Muslim ethnic minorities.

Those added to the so-called “Entity List” include the Xinjiang Uighur Autonomous Region People’s Government Public Security Bureau, 19 subordinate government agencies and eight commercial firms, according to a Commerce Department filing. The companies include Zhejiang Dahua Technology, IFLYTEK Co, Xiamen Meiya Pico Information Co and Yixin Science and Technology Co.

The department filing said the “entities have been implicated in human rights violations and abuses in the implementation of China’s campaign of repression, mass arbitrary detention, and high-technology surveillance against Uighurs, Kazakhs, and other members of Muslim minority groups.”

The list includes municipal and county public security bureaus and the Xinjiang Police College.

US officials said the announcement was not tied to this week’s resumption of trade talks with China. Being added to the “Entity List” bars companies or other entities from buying parts and components from US companies without US government approval.

The Commerce Department previously added Huawei Technologies Co and more than 100 affiliates to the Entity List.

Hikvision, officially known as Hangzhou Hikvision Digital Technology Co Ltd, with a market value of about $42bn, calls itself the world’s largest video surveillance gear maker. Reuters reported in August Hikvision receives nearly 30% of its 50 billion yuan ($7 billion) in revenue from overseas.

Hikvision did not immediately comment on the Commerce Department’s move. The Chinese embassy in Washington also did not immediately comment.

In April, a bipartisan group of US lawmakers urged the move against Chinese companies it called “complicit in human rights abuses” and specifically cited Hikvision and Dahua.

China faces growing condemnation from Western capitals and rights groups for setting up facilities that UN experts describe as mass detention centres holding more than one million ethnic Uighurs and other Muslims.

US Secretary of State Mike Pompeo said last week at the Vatican that “when the state rules absolutely, it demands its citizens worship government, not God. That’s why China has put more than one million Uighur Muslims ... in internment camps and is why it throws Christian pastors in jail.”

John Honovich, founder of surveillance video research company IPVM, said Hikvision and Dahua both use Intel Corp , Nvidia Corp, Ambarella Inc, Western Digital and Seagate Technology as suppliers and that the impact on the Chinese companies would be “devastating.” Shares in Ambarella fell 12% in after-hours trading on the news.

In August, the Trump administration released an interim rule banning federal purchases of telecommunications equipment from five Chinese companies, including Huawei and Hikvision.

Huawei has repeatedly denied it is controlled by the Chinese government, military or intelligence services and has filed a lawsuit against the US government’s restrictions.