Meadowhall in Sheffield has been named in a list of shopping centres, museums and conference centres around the UK where facial recognition technology has been used, an investigation has claimed.
Civil liberties group Big Brother Watch labelled use of the technology an "epidemic" and said its use on privately owned sites was "deeplydisturbing".
The group said the Meadowhall shopping centre had carried outtrials of the technology last year, while the World Museum in Liverpool andMillennium Point conference centre in Birmingham were also named in itsinvestigation as locations where scans had taken place.
The Information Commissioner's Office announced it would launch its own investigation into the use of facial recognition cameras.
The UK's data and privacy watchdog said it was "deeply concerned about the growing use of facial recognition technology in public spaces" and is seeking "detailed information" about how it is used.
Big Brother Watch chief executive Silkie Carlo said increasing use of the technology was placing personal privacy at risk.
"There is an epidemic of facial recognition in the UK," she said.
"The collusion between police and private companies in building thesesurveillance nets around popular spaces is deeply disturbing. Facial recognition is the perfect tool of oppression and the widespread use we've found indicates we're facing a privacy emergency.
"We now know that many millions of innocent people will have had their faces scanned with this surveillance without knowing about it, whether by police or by private companies."
The group's investigation reported that the Meadowhall shopping centre carried out a trial last year and the site's owner British Land also has sites in parts of London including Paddington, Broadgate, Canada Water and Ealing Broadway.
Meadowhall's owners said: "We do not operate facial recognition at any of our assets.
"However, over a year ago we conducted a short trial at Meadowhall, in conjunction with the police, and all data was deleted immediately after the trial."