Police in West Yorkshire are planning to use Bluetooth to alert people that criminals are lurking behind every tree and they should lock their doors and windows.

Apparently, one in four burglaries is carried out by an opportunist, noticing an open door and brazenly walking through it. Unsurprisingly, the incidence of such theft rises with summer temperatures.

West Yorkshire police will be printing 80,000 leaflets, 200 posters, and 50,000 beer mats to let people know they should secure their homes, as well as sending messages over Bluetooth to nearby telephones.

The system was developed by Innovation Leeds, part of Leeds City Council's ICT Department, and uses a phone to poll for Bluetooth devices within 30 feet, then sends a message: "1 in 4 Through An Unlocked Door – Stop The Sneak".

Given the (albeit minimal) risk of leaving Bluetooth switched on, a better message might read "Beware of Blue Snarfing - switch off Bluetooth now".

At 30 feet away the police could just shout their message out loud, but that wouldn't be nearly as much fun. ®