Tourists, shoppers and office workers on a busy London street on an ordinary weekday found themselves part of a digital identity check as live facial recognition cameras scanned faces against a police watchlist.

The operation was an example of a technology the Metropolitan Police say is transforming policing, helping officers arrest around 2,500 wanted people since the start of 2024, including suspects accused of violent and sexual offences.

Critics, however, say live facial recognition undermines the presumption of innocence underpinning British law by treating every ?passerby as a potential suspect.