The inventor of a bomb detection device that the US Army described as working "on the same principle as a Ouija board" has been arrested after a court ruled that it was fraudulent, and banned it from sale.

The ADA-651 comprises a plastic grip, an antenna and a wire that leads to an RFID card reader. Different cards can be slotted into the reader which can then be used to detect different items up to a kilometre away - from TNT and plastic explosive to money and elephants. However, the BBC's Newsnight program investigated, opened up  the cards, and discovered that they just contain a dumb RFID tag.

Inventor Jim McCormick sold thousands of the devices to the Iraqi government, who spent $40,000 per unit. McCormick says: "We have been dealing with doubters for 10 years. One of the problems we have is that the machine does look a little primitive. We are working on a new model that has flashing lights".

The ADE-651 has been banned from export, as has similar devices. McCormick has been arrested on suspicion of fraud by misrepresentation, but has now been released on bail. The police said: "We are satisfied the bomb detectors don’t work".