nk497 writes "As the price of copper rises, thieves have taken to stealing broadband cables, taking out internet connections and slowing down the rollout of super-fast broadband by giving engineers more work to do. To battle the criminals, UK provider BT has 21 investigators on staff to track down thieves and has started using SmartWater bombs that spray stolen property and the criminals. The SmartWater liquid carries a DNA fingerprint that links a criminal to the scene of the crime and police units carrying ultra-violet light detectors can use the incriminating stains to make an arrest after the trap has been sprung. 'We had one case recently where someone in Dagenham was stopped and searched after acting suspiciously and the police used a UV light on them and could show that they had been tampering with the equipment,' said Auguste. The SmartWater liquid can also be pasted inside cables, making them easier to trace — and less appealing to scrap metal buyers, helping to cut demand for stolen copper."