Sony Corp. and Sharp Corp. have supplied parts to video surveillance company Hangzhou Hikvision Digital Technology Co., one of 28 Chinese entities blacklisted by the United States last month over human rights violations, the Chinese company's product brochures show.

Hikvision -- the world's largest video surveillance company -- employs image sensors supplied by Sony in 180 of its surveillance camera models and sensors from Sharp in two camera models, according to its product brochures.

The company previously stated on its website that one of its surveillance camera models could identify members of the Uyghur ethnic minority group, but it removed the product from the website after the company was added to the U.S. trade blacklist.

Communist Party documents obtained by the International Consortium of Investigative Journalists have revealed that China has deployed a surveillance and predictive-policing system in its crackdown on Uyghurs and other Muslims minorities in China's far-western Xinjiang autonomous region.

BBC video footage has shown Hikvision surveillance cameras installed in a Chinese detention center for Uyghurs.

(File photo)

A Sony spokesperson said the company does not comment about its customers but its basic policies include respect for human rights. Sharp said it does not disclose information about its customers.

The United States added 28 Chinese public security bureaus and firms including Hikvision to the blacklist, saying they had been implicated in "the implementation of China's campaign of repression, mass arbitrary detention, and high-technology surveillance" targeting Uyghurs and other predominantly Muslim minority groups in Xinjiang.

Honda Motor Co., which has teamed up with blacklisted facial recognition company SenseTime Group Ltd. for self-driving technology, said it will continue the joint research.

Eiken Foundation of Japan, operator of a private-sector English proficiency test, said it had discontinued a joint study with voice recognition firm Iflytek Co., which was also added to the list, though it declined to elaborate.

Hajime Kuramochi, associate professor at Tohoku University of Community Service and Science, said the limited discussion in Japan of human rights means local companies are less active in addressing such issues.

"Japanese companies' awareness of human rights lags 20 years behind U.S. and European companies," he said.

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