US police is developing an infrared body scanner that can detect whether a suspect is carrying a weapon without needing to frisk him.

Infrared rays will be used to scan a form of natural energy – like radiation – emitted from the body of someone concealing a gun on the street.

If something is obstructing the flow of that energy, such as a weapon, the gadget will show exactly where the object is on a suspect’s body.

As a result, officers will get a digital outline of where the firearm is. The device could also be used to find suicide bomber vests, Newsday reported.

Infrared rays will be used to scan a form of natural energy - like radiation - emitted from the body of someone concealing a gun on the street

The New York Post reported that the device has been undergoing development for the past three years for the streets of New York City.

The device will be mounted on the top of NYPD vans and will shoot rays at a suspect or scan the streets for weapons.

Police Commissioner Raymond Kelly said it currently only works at a short range – from around three to four feet away from a person.

“This can be done from a short range,” Raymond Kelly said.

“We want a distance of at least 25 meters.”

Commissioner Raymond Kelly said the department is working with the U.S. Department of Defense to develop the device.

The gadget would mean the NYPD would no longer have to stop and frisk those suspected of carrying weapons – a practice which rocketed by 13% last year.

Yet there are also concerns that the gadget could be an invasion of privacy as they show an outline of a suspect’s body – similar to “naked” body scanners used in airports.

It comes as the NYPD is set to develop a new range of futuristic technology to avoid fire between its own ranks.

Raymond Kelly asked his officers to brainstorm ideas following the death of Omar J. Edwards, 25, when he was shot while off duty last week.

Omar J. Edwards had left work when he witnessed a burglary, drew his weapon and chased the suspect. Police responding to the call shot him dead.

One idea for the protective gadgets uses radio frequency tags to show officers where other cops are in the city.

Another involves tags that would work gun-to-gun and use an infrared sensor.

When a weapon is pulled from an officer’s holster it would trigger a signal – seen or heard – that would be sent to the gun of a nearby officer.