"A FUNDAMENTAL tool in the fight against crime" - that is how police have described state-of-the-art tracking devices which have so far led to the arrest of 18 sat nav thieves.

The Press told last month how police were using sophisticated technology to catch thieves red-handed.

In elaborate sting operations they are planting pricey satellite navigation systems, fitted with tracking technology, in unmarked cars across the city and waiting for thieves to strike.

Police arrested 13 people the first 17 times they used the technology. The devices have now been used a further 12 times, leading to the arrest of five more offenders.

Chief Inspector Nick Warnes said: "This is one of the most effective tools we are using to target offenders.

"We do lots of work to try to educate people not to become victims, but the real impact we have is when we start catching offenders.

"Inevitably there will always be somebody who leaves something in a car for whatever reason and it's difficult to protect those people. The best way we can do that is by catching offenders and that's what makes this such a fundamental tool in the fight against crime.

"We are continuing to deploy the tracker system and using it in all kinds of property and different situations - not just theft from cars."

A soon as the device is moved, a signal is sent from the sat nav to a portable computer and police use it to track down the unsuspecting thief - or the person who has bought the gadget - within half an hour of it being stolen.

The signal is so good officers can track the device's exact position - even to within a specific drawer within a room of a house.

Chief Insp Warnes added: "I would warn anybody who thinks about buying a sat nav, if they don't know where it's come from, they have got to ask themselves how do they know it's not a tracker system and that ten minutes later the police won't be knocking at their door."

He said they could get a much tougher penalty for handling stolen goods than for theft.

Police believe some sat navs are being stolen to order and that people are buying stolen £500 sat navs for prices between £90 and £100.

The Press told last week how more than 12 sat nav systems a week were still being stolen in York.

Figures showed 117 of the devices had already been stolen from cars and vans this year.

Sat nav theft is a long-running problem for police in the city, who have a target to cut vehicle crime by more than 30 per cent by March 2010.

At its peak, in October last year, sat nav thefts rocketed to almost six a day.

How the sting works

IN the first week of February, a car in Huntington, York, was broken into and a tracked sat nav was stolen. Two teenagers were caught by police and arrested. A week later, a sat nav was stolen from a parked car in Heworth. The tracking device led police to a house in the area and the occupant was arrested.

They were then deployed a further eight times in the Clifton, Clifton Moor and New Earswick areas, but they were not stolen. At the beginning of March, the sting was used again in the Heworth area and the sat nav was found at the home of another man who was arrested.