A UK company is marketing the first CCTV camera that can see objects under a person's clothing.

The ThruVision T5000 can spot items underneath clothing at a range of up to 25 metres.

All materials emit different terahertz waves, allowing the cameras to differentiate between sugar and cocaine, for example.

Clive Beattie, chief executive at ThruVision, said: "Acts of terrorism have shaken the world in recent years and security precautions have been tightened globally.

"The ability to see metallic and non-metallic items on people out to 25 metres is a key capability that will enhance any comprehensive security system deployment."

ThruVision claimed that privacy campaigners should not be alarmed since the human body emits terahertz waves at a frequency which the device does not scan, meaning that personal body details are not revealed.

This contrasts with millimetre wave radar such as the Secure 1000 systems being tested at Heathrow which provide clear pictures of the body under clothing.

Dr Liz Towns-Andrews, director of knowledge exchange at the Rutherford Appleton Laboratory, said: "Astronomers use T-ray cameras that can see through dust and clouds in space, revealing what lies beyond.

"This is a first-class example of how fundamental scientific research can be applied to benefit the whole of society.

"Who would have imagined that research carried out by space scientists to study the stars could be used to protect the public from terrorists and therefore save lives? The impact of this will be remarkable."