The Metropolitan police gave watch list images to private developers at Kings Cross, allowing them to use facial recognition on the public, it has been revealed.

The police force previously said it had not shared images for facial recognition with any private companies, but has since admitted this was “incorrect”.

The decision was taken by local police, and was not brought to the attention of the Met’s central image-sharing team, the force has said.

Police also acted without the knowledge of the Mayor, Sadiq Khan, who was not aware the contentious technology was being used at Kings Cross prior to reports breaking in the press last month.

Developer Argent – a partner company in Kings Cross Limited – admitted using facial recognition on its 67-acre site, in a story broken by the Financial Times.

The technology matches live CCTV images of the public with a database of known pictures – it was these that were supplied by police, although it is not clear what the criteria were for including individuals on the list.

The revelations of Met involvement came in an update to a Mayoral question asked by Green assembly member Sian Berry, regarding police facial recognition partnerships with private companies.

Her question followed revelations that Manchester police worked with the owners of a major shopping centre in the city to use the controversial technology on shoppers.

In his August response to Ms Berry, the Mayor said the Met “has not worked with any retailers or private sector organisations who use Live Facial Recognition, neither do we have any current plans to do so.”

But an update on Wednesday revealed that the police “shared images related to facial recognition” with Kings Cross Limited.

Mr Khan described the revelation as a “concerning development” and said he had requested a report into the incident and the wider data-sharing practice of the Met “as a matter of urgency”.

Ms Berry – who is co-leader of the Green Party and a Mayoral candidate – said that misleading both her and the Mayor was “a serious matter”.

She said: “If local police have been given no guidance about sharing biometric data and photographs with people who are going to use facial recognition then that’s a very serious failure on the part of the Met.”

She added: “If you’re going to use sinister technologies that infringe people’s human rights […] and the police are not being transparent – if they’re giving false answers and they’re not taking good care of people’s data – that is a definite concern and needs to be addressed.”

Ms Berry said the Mayor and the Mayor’s Office for Policing and Crime (MOPAC) should be doing more to protect Londoners from potentially illegal uses of facial recognition.

She said: “They should be right on top of this, looking after our human rights and being the most diligent people in London – not leaving it up to Assembly Members like me.”

A spokesperson for the Met said the decision to share images with Kings Cross developers had only now come to the attention of its central team.

She said: “Prior to spring 2018, the Metropolitan Police Service shared images, for the purposes of facial recognition to assist in the prevention of crime, with the Kings Cross Estate team under a local agreement developed between local police and the partnership.

“This ceased in Spring 2018. The Metropolitan Police Service has not shared any images with the Kings Cross Estate, or any related company, for facial recognition purposes since March 2018.”