A mass rollout of body-worn cameras to more than 22,000 Met Police officers begins today.

The deployment, described as the largest of its kind by police anywhere in the world, follows trials that began in 2014 in 10 boroughs including Bexley, Bromley, Croydon and Lewisham.

Over the coming months, the cameras will be issued to all 32 London and other frontline specialist roles, including overt firearms officers.

The Met said the cameras have already shown they can help bring about speedier justice for victims, and have been particularly successful in domestic abuse cases where there has been an increase in earlier guilty pleas from offenders who know their actions have been recorded.

Scotland Yard said: "The technology offers greater transparency for those in front of the camera as well as behind it.

"Londoners can feel reassured during their interactions with the police, whilst allowing us to demonstrate the professionalism of our officers in the many challenging and contentious interactions, such as the use of stop and search."

The cameras will be attached to the officer's uniform and will not be permanently recording.

MORE: Met Police to get 20,000 body cameras as video technology is rolled out across capital

Police said members of the public will be told as soon as practical that they are being recorded, and when the camera is recording it is highly visible - notable by a flashing red circle in the centre of the camera and a frequent beeping noise when the camera is activated.

Met Commissioner Sir Bernard Hogan-Howe said: "Body Worn Video will support our officers in the many challenging situations they have to deal with, at the same time as building the public's confidence.

"What we do every day will be seen by the public - that has to be good.

"Our experience of using cameras already shows that people are more likely to plead guilty when they know we have captured the incident on a camera. That then speeds up justice, puts offenders behind bars more quickly and most importantly protects potential victims.

"Video captures events in a way that can't be represented on paper in the same detail, a picture paints a thousand words, and it has been shown the mere presence of this type of video can often defuse potentially violent situations without the need for force to be used."

Mayor of London Sadiq Mr Khan, who joined the Commissioner in Lewisham to launch the rollout, said the technology brings the police force "into the 21st century".

In November 2015, the Mayor's Office for Policing and Crime (MOPAC), awarded a three-year contract worth £3.4 million to Axon Public Safety UK Limited to supply the Met with 22,000 cameras.

Last month, a study by the University of Cambridge found a 93 per cent decrease in complaints made against officers clearly wearing body cameras.