Chinese police are using sunglasses equipped with facial recognition technology at a train station in Zhengzhou, leading to fears that such technology might be used to track more than just criminals.
The technology allows police officers to take a photograph of a suspicious individual and then compare it to pictures stored in an internal database. If there is a match, information such as the person's name and address will then be sent to the officer.
Authorities say the sunglasses have led to seven arrests, along with identifying 26 individuals using fake IDs.
China leads the world in terms of facial recognition technology, and advances in the government's surveillance technology have made it all but impossible to elude authorities.
The country has been building what it calls "the world's biggest camera surveillance network".
An estimated 170 million CCTV cameras are already in place and some 400 million new ones are expected be installed in the next three years.
Many of the cameras use artificial intelligence, including facial recognition technology.
Such techniques have created fear that the Chinese government will use this technology to track political dissidents or profile ethnic minorities.