When thousands of football fans pour into Cardiff's Principality Stadium on June 3 to watch the final match of the UEFA Champions League, few will be aware that their faces will have already been scanned, processed, and compared to a police database of some 500,000 "persons of interest". According to a government tender issued by South Wales Police, the system will be deployed during the day of the game in Cardiff's main train station, as well as in and around the Principality Stadium situated in the heart of Cardiff's central retail district. Cameras will potentially be scanning the faces of an estimated 170,000 visitors plus the many more thousands of people in the vicinity of the bustling Saturday evening city center on match day, June 3. Captured images will then be compared in real time to 500,000 custody images stored in the police information and records management system alerting police to any "persons of interest," according to the tender. The security operation will build on previous police use of Automated Facial Recognition, or AFR technology by London's Metropolitan Police during 2016's Notting Hill Carnival.

Police in Wales plan to use facial recognition on fans during the Champions League final in Cardiff on 3 June, according to a government contract posted online. Faces will be scanned at the Principality Stadium and Cardiff's central railway station. They can then be matched against 500,000 "custody images" stored by local police forces. South Wales Police confirmed the pilot and said it was a "unique opportunity". A report on the plan was first posted by tech news site Motherboard.

If you're headed to the UEFA Champions League final in Cardiff on June 3rd, you might just be part of a massive experiment in security -- and a privacy uproar. South Wales Police are conducting a face recognition trial that could scan every one of the 170,000 visitors expected to show up in the city for the match, whether or not they're heading to the stadium. Cameras around both the stadium and Cardiff's main train station will compare faces against a police database of 500,000 people of interest. If there's a match, police will get a heads-up that could help them stop a terrorist or frequent hooligan. The UK's surveillance camera commissioner, Tony Porter, tells Motherboard that the South Wales Police will have to honor the country's usage guidelines.