Facial recognition technology in shops will soon alert police in real time to the presence of serious offenders, with civil liberties groups warning of a “dangerous escalation” towards surveillance and criminalisation in the retail sector.

Facewatch, a facial recognition system used by more than 100 businesses including Sainsbury’s, B&M and Spar to monitor thieves, said it was launching a UK-first feature to “alert police instantly when the most serious offenders trigger a live facial recognition match”.