THIEVES have begun targeting cars in Edinburgh for their expensive satellite navigation systems.
Police warned today that more than 70 of the computer kits have been stolen from vehicles in the Capital in the last three months.
They say the systems have become the latest "must-steal" items for criminals and are targeted almost as often as mobile phones and car stereos.
Police are now appealing to drivers not to leave the equipment - which typically costs around 200 - on view in their cars.
Sergeant Annette Wayte, of Lothian and Borders Police's safer communities department, said: "The kits are an easy target if they are left out in the open.
"The thieves just smash the car window and they're away in seconds.
"Most of the stolen kits had been left in plain sight, but there are cases where they've been taken from glove boxes. The thieves have spotted the dashboard cradle and the glove box was the first place they checked.
"Our advice is to remove the system from the car altogether when you're not driving. You shouldn't leave any expensive items in your car unattended.
"Drivers should also remove any stickers which indicate your vehicle is fitted with a sat-nav."
The appeal comes in the run-up to Christmas, when hundreds of city motorists are expected to receive the kits as gifts.
The systems are becoming increasingly popular, with UK drivers spending 305 million on sat-nav technology last year, up 510 per cent on 2003.
But the black market in the kits has topped 13m annually, with systems being sold on for as little as 50 by smash-and-grab thieves.
In Edinburgh, thieves made off with 23 kits in August, 30 in September, 18 in October and five so far this month.
In West Lothian, police officers have investigated nine similar thefts in the last two weeks.
Sgt Wayte said that systems could be marked with ultraviolet pens to make them easier to trace back to the owner if they are recovered.
She added: "You should keep a note of your system's serial number, make and model to ensure you have as much information as possible should you be a victim of theft.
"With Christmas coming up, we're expecting many more drivers to be using these kits. Sensible precautions will ensure they are not stolen and the owners do not suffer the added inconvenience of having to get their broken windows repaired.
"And anyone being offered these kits in a pub or anywhere else at knock-down prices can be reasonably sure they were stolen."
Neil Greig, policy chief with the AA, said: "These thefts are something we've been highlighting for a while because it's a growing problem. Car crime in general has been going down over the years, but there has been a recent blip and we put that almost entirely down to sat-navs. They are very small, valuable and sellable.
"Car crime nowadays is not about stealing cars. It's about stealing expensive items from inside. We've been pushing manufacturers to introduce a simple pin number system, much like mobile phones, to make them worthless if they are stolen."