Police used a remote-controlled "flying saucer" to monitor the BNP's Red, White and Blue festival in Codnor, Derbyshire, where anti-fascist protesters have assembled.
Similar to a mini-helicopter, the device has four pairs of carbon-fibre rotor blades which support a camera. An operator on the ground controls the vehicle's flight using a hand-held control panel with two joysticks.
The drone – which is based on military Unmanned Aerial Vehicle (UAV) technology – feeds live images back to a screen on the control unit, enabling the "pilot" to operate the machine even when it is out of his or her sight.
Bron: telegraph.co.uk