The tool enables cops to compare faces captured on a live camera feed to people on its pre-determined watchlist.

Norfolk Police to launch Live Facial Recognition in Norwich (Image: Andrew Matthews/PA)

Officers say this will help them find people who pose a risk to the public, who are wanted by the police or the courts or who have court orders.

But civil liberty campaigners have called for the police to abandon its plans of the "intrusive technology more suited to authoritarian regimes".

Jasleen Chaggar, from Big Brother Watch - an organisation which campaigns against surveillance and censorship - said: "Norwich residents should not be subjected to invasive biometric face scans.

Jasleen Chaggar is the senior legal and policy officer at Big Brother Watch (Image: Supplied by Jasleen Chaggar)

Police say the van will be marked and the recognition area will be clearly signposted (Image: Danny Lawson/PA)

"The alarmingly broad categories of people who can be added to a police watchlist, including those linked to non-crimes and even victims of crime, are open to abuse.

"Police use of live facial recognition cameras around the country has resulted in legal challenges, misidentifications and hundreds of officer hours spent staring at screens rather than frontline policing work.

"Norfolk Constabulary should abandon its plans to deploy this intrusive technology, more suited to authoritarian regimes than a democracy, especially while there is still no clear law governing its use."

The technology, which is being deployed in the city centre, involves using a marked van in a recognition zone the police say will be clearly signposted.

It relies on biometric data which is taken by mapping out faces within the recognition zone and taking measurements of facial features, which are then compared against the police's watchlist.

The technology uses data by scanning faces to alert the police of a watchlist match (Image: Jordan Pettitt/PA)

If there is a match, the system alerts the police who will then review the alert, carry out further checks to determine if the person is a suspect and take appropriate action.

Inspector Toby Gosden said: "We have seen how successful the technology has been in other forces around the country and are looking forward to replicating the results in Norfolk.

"Our officers will not be monitoring the daily business of the local community but instead working to secure justice for victims of crime and finding dangerous people on our streets."

The term 'Big Brother' comes from George Orwell's dystopian novel Nineteen Eighty-Four.

In the book, Big Brother is an all-seeing leader in the totalitarian state of Oceania and the slogan "Big Brother is watching you" appears on propaganda posters.

The term has become a symbol for state surveillance and the character inspired a reality TV series of the same name.

In the series, contestants called "housemates" live together in a specially constructed home isolated from the outside world where they are monitored during their stay.

© Norwich Evening News