A camera system that uses AI and facial recognition intended to reveal emotional states has been tested on Uyghurs in Xinjiang, the BBC has been told.
A software engineer claimed to have installed such systems in police stations in the province.
A human rights advocate who was shown the evidence described it as shocking.
The Chinese embassy in London has not responded directly to the claims but says political and social rights in all ethnic groups are guaranteed.
Xinjiang is home to 12 million ethnic minority Uyghurs, most of whom are Muslim.
Citizens in the province are under daily surveillance. The area is also home to highly controversial “re-education centres”, called high security detention camps by human rights groups, where it is estimated that more than a million people have been held.
“The Chinese government use Uyghurs as test subjects for various experiments just like rats are used in laboratories,” he said.
And he outlined his role in installing the cameras in police stations in the province: “We placed the emotion detection camera 3m from the subject. It is similar to a lie detector but far more advanced technology.”
He said officers used “restraint chairs” which are widely installed in police stations across China.
“Your wrists are locked in place by metal restraints, and [the] same applies to your ankles.”
He provided evidence of how the AI system is trained to detect and analyse even minute changes in facial expressions and skin pores.