Millions of people face the prospect of being scanned by police facial recognition technology that has sparked human rights concerns.
The controversial software, which officers use to identify suspects, has been found to be “staggeringly inaccurate”, while campaigners have branded its use a violation of privacy.
But Britain’s largest police force is set to expand a trial across six locations in London over the coming months.
Police leaders claimed officers make the decision to act on potential matches with police records and images that do not spark an alert are immediately deleted.
But last month The Independent revealed the Metropolitan Police’s software was returning “false positives” – images of people who were not on a police database – in 98 per cent of alerts.
The technology, which has previously been used at Notting Hill Carnival and Remembrance Sunday services, was used on thousands of shoppers in Stratford, east London.
Scotland Yard said the Stratford operation would be “overt” and that members of the public passing the cameras would be handed leaflets, but The Independent did not observe any information being proactively given out.
The majority of those passing through a line of police officers straddling a bridge appeared not to see posters saying facial recognition technology was being used through the throngs of shoppers.
Sophia Pharaoh said she felt “uncomfortable” knowing the software was in use at the busy intersection, which sits between two shopping centres near Stratford Tube and railway station, adding: “It’s an invasion of privacy and there’s no way around it.”
Maya, a local resident who did not want her surname published, said she understood why police were trialling the new technology amid a nationwide rise in violent crime, but continued: “If they are doing that, people need to be aware of the reasons behind it. People need to understand what’s going on.”
Her boyfriend, Zee, believed facial recognition could make London safer but said: “If they are using it people should know, and they’re not aware. Hopefully it will bring benefits – the last thing we want to hear about is another murder or stabbing.”
Stratford, which was the site of major regeneration projects ahead of the London 2012 Olympics, has suffered a string of violent attacks, fights and robberies mirroring a wider uptick in violence.
In March a 21-year-old man was stabbed to death in the Stratford Centre and in September, another man was knifed during a “mass brawl” at neighbouring Westfield.