(CNN) -- London's Metropolitan Police has announced controversial plans to use live facial recognition technology to improve officers' ability to identify suspects and police the British capital.

The Met said in a statement Friday the technology will be deployed to places where data indicates people responsible for serious and violent crimes, such as gun and knife attacks and child sexual exploitation, are most likely to be located. Clearly marked cameras will be focused on small, targeted areas to scan people's faces as they walk by, it added.

"As a modern police force, I believe that we have a duty to use new technologies to keep people safe in London," assistant commissioner Nick Ephgrave said in a statement. "We are using a tried-and-tested technology. Similar technology is already widely used across the UK, in the private sector," he added.

The technology, which is made by Japanese company NEC, is a standalone system not linked to any other imaging system, such as closed-circuit television, body worn video or automatic number plate recognition, the Met said.

The decision follows an October investigation into live facial recognition technology by the UK's Information Commissioner's Office, which raised serious concerns over privacy and accuracy. It flagged evidence that the technology discriminates against women and people of color -- an issue that's been documented by Federal researchers in the United States, where several cities have banned use of the technology.

"Moving too quickly to deploy technologies that can be overly invasive in people's lawful daily lives risks damaging trust not only in the technology, but in the fundamental model of policing by consent," Elizabeth Denham, the UK's Information Commissioner, said at the time.

In the United States, some California cities including San Francisco and Oakland, as well as Somerville, Massachusetts, have decided the risks of facial recognition technology outweigh the benefits and banned its use by city departments. India, on the other hand, has used the technology to find missing children and wants to build the world's largest facial recognition system.

Denham's office on Friday called on government to urgently introduce laws to govern live facial recognition. "We have received assurances from the [Metropolitan Police] that it is considering the impact of this technology and is taking steps to reduce intrusion and comply with the requirements of data protection legislation," the commissioner's office said in a statement.

Advocacy groups warned democratic freedoms would be undermined.

"This decision represents an enormous expansion of the surveillance state and a serious threat to civil liberties in the UK," Big Brother Watch director Silkie Carlo said in a statement Friday.

"Facial recognition technology gives the State unprecedented power to track and monitor any one of us, destroying our privacy and our free expression," Liberty's advocacy director, Clare Collier, said in a statement.

The Met said it will engage with local communities before deploying the technology.

This story was first published on CNN.com, "London will use live facial recognition cameras to police the city"