Deployments of surveillance vans over five months result in nine false alerts and led officers to engage with 146 registered sex offenders

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More than a million people have had their faces scanned in a trial of real-time facial recognition technology in Western Australia, resulting in 122 arrests and nine incorrect alerts.

WA police said under the five-month trial, which concluded on Saturday, the technology scanned 1,380,882 faces after 100 deployments across 43 regional and metropolitan locations.