It may look like a child's toy but this unmanned spy helicopter can swoop down and squirt criminals with a liquid marker so they can later be identified by police.
The £25,000 remote-controlled Microdrone, the size of a dustbin lid, can capture high-quality video footage and infrared imagery from more than 350ft away, beaming the data back to its operators on the ground.
But its most revolutionary function is to mark offenders with a solution called SmartWater which identifies them to police.
Take that! The Microdrone unmanned spy helicopter not only photographs criminals but also douses them in an identifying fluid
British Transport Police have been using the device, which took eight years to develop, as part of an operation to crack down on metal cable thefts on the railways, codenamed Operation Drum.
A BTP spokesman said: "Although it may look simple, it's actually a complex bit of kit capable of many things.
"There's only one being used at the moment as it is an expensive device."
Police Constable Roy McMichael, who is co-ordinating Operation Drum in Warwickshire, said: "The Microdrone is an excellent piece of technology which is assisting BTP in our ongoing fight against cable thieves.
Metal theft ...   more »