Authorities in northwest China’s volatile Xinjiang region are expanding their monitoring of the region’s mostly Muslim Uyghurs, moving beyond surveillance cameras and facial-recognition systems to implement a “big data” system designed to predict offenses, an international rights group said in a report released Tuesday.



The system draws information from multiple sources—including police reports, vehicle checkpoints, banking and health-care records, and technological collection systems—into a single program for police reference, Human Rights Watch (HRW) said in its report, titled “China: Big Data Fuels Crackdown in Minority Region.”



This “big data” program, called the Integrated Joint Operations Platform (IJOP), then aggregates the collected information and flags individuals considered a potential threat to Chinese control, HRW said.



“For the first time, we are able to demonstrate that the Chinese government’s use of big data and predictive policing not only blatantly violates privacy rights, but also enables officials to arbitrarily detain people,” Maya Wang, senior China researcher at HRW, said in its report.



“People in Xinjiang can’t resist or challenge the increasingly intrusive scrutiny of their daily lives because most don’t even know about this ‘black box’ program or how it works,” Wang said.



Already monitored in their daily lives by a vast network of cameras, Uyghur residents are now also subject to frequent visits at their homes by police, who note down signs of “unusual” activity or “untrustworthy” political or cultural views, including indications of “religious extremism,” HRW said.



“One interviewee said that possession of many books, for example, would be reported to IJOP, if there is no ready explanation, such as having teaching as one’s profession,” the rights group said in its report.



Electricity and phone use are also checked, together with purchasing habits, HRW said, adding that some of those flagged by IJOP are detained and sent to political re-education centers, where they are held indefinitely “without charge or trial.”



Sources interviewed by HRW said they had once observed the IJOP computer “generate lists of individuals to be rounded up by the police,” the rights group said.



“One heard police saying that some of those on the list would be detained and/or sent to political education centers,” HRW said.



Around 120,000 ethnic Uyghurs are currently being held in political re-education camps in Xinjiang’s Kashgar (in Chinese, Kashi) prefecture alone, a security official with knowledge of the situation told RFA in January.



Xinjiang—where Uyghurs complain of pervasive discrimination, religious repression, and cultural suppression under Chinese rule—has become one of the world’s most heavily policed places and a testing ground for increasingly restrictive policies since the region’s party chief Chen Quanguo was appointed to his post in August 2016.