The laser, developed by a former Royal Marine commando, temporarily dazzles anyone who looks at it.

The shoulder-mounted laser can temporarily impair vision and incapacitate people up to 500m away with its three square metre wall of light.

It costs £25,000 and has infrared features so police can spot looters at night.

Troops in Afghanistan have used similar devices against insurgents.

Paul Kerr, managing director of British-based Photonic Security Systems, the firm behind the device, said: “The system would give police an intimidating visual deterrent. If you can’t look at something you can’t attack it.

“If police spot someone trying to do something untoward, painting them with this would certainly make them think twice about it.”
He also added that it could be used during hostage rescues.

A spokesman for the Home Office said the technology needs to be tested to make sure it doesn’t cause any permanent damage to people before it can be used.

Kerr added: “The quality and safety of the device is paramount and I know that first hand because I have been the guinea pig many times. I know what it is like and I know how effective it can be.”

The police were criticised this summer for being ill-equipped to deal with unrest in British cities.

The Home Office is testing a number of devices to deter rioters because of the growing number of violent situations facing the police, including long-range chemical irritant projectiles.

The Metropolitan police is also increasing the number of officers that are trained to shoot plastic bullets, warning that they could be used if rioting gets out of hand.