NORTH and West Yorkshire police officers are joining forces to crack down on cross-border criminals travelling across the county to steal expensive cars.

Crooks from both areas have been targeting homes with high-performance vehicles on their drives by breaking into the property to steal the car keys then making off with the vehicle.

Thieves find this method particularly effective because modern cars are difficult to steal, due to high-tech security devices, like electronic immobilisers, where only the key can be used to start the engine.

DS Dave Horne, of Harrogate CID said patrols in Harrogate and Selby would be stepped up to help combat the spate.

"Over the last 12 months we have experienced numerous occasions of criminals travelling across both North and West Yorkshire to commit offences," said DS Horne.

"In particular they are breaking into houses in order to steal car keys which they then use to steal the vehicle concerned, usually from outside the owner's home address.

"I would much prefer these people to stay at home, but if they insist in coming into our county to commit crime, they know that we are waiting for them."

Overnight on Tuesday, thieves broke into a house at Beckside, Elvington, to steal a Subaru Impreza and VW Passat.

In Ryedale, burglars broke into a home at The Mount, Malton, between 2.50am and 3am on Thursday, and stole keys to a green Jaguar XKR registration J15 XKR, then made off with the £35,000 vehicle.

Thieves broke into a home at Newbiggin, Malton, between 10.20pm on November 21 and 8.40am the next day to steal an Audi A4 worth £17,000.

Malton CID have issued advice to car owners following the spate of high performance vehicle theft.

DC Gary Riddler said car owners should not leave keys out where they could be easily seen, for example on hooks hanging by the door or on kitchen work surfaces. And people should park their cars in garages, use alarms and security devices.

Anyone with information about the crimes should call DC Riddler at Malton CID on 01723 509662.

Updated: 09:59 Monday, December 01, 2003