Car thieves have found a way to steal vehicles 'by remote control' - by redirecting the electronic signal from a key fob in the owner's house.
Motorists with modern keyless entry cars have been warned by gardaí to be extra vigilant and take a number of easy security precautions.
More than 10pc of vehicles stolen in Ireland this year are being taken by criminals who have never gained access to the keys.
They use a reading device, which redirects the wireless signal from the key fob, stored inside the house at night, to the vehicle. This allows them to start the vehicle and make off with it.
As the technique becomes more popular, some car owners are putting their keys in the microwave or the freezer to block the signal.
A total of 139 vehicles have been stolen nationwide in the first nine months of this year through the use of redirected signals, according to unpublished Garda statistics.
The majority of those thefts have taken place at properties in Co Dublin and Co Kildare, and the criminals' targets of choice are usually Nissan, BMW and Toyota models.
But one particular gang operating in Northern Ireland has concentrated on high-end marques including Range Rover and Land Rove.
Sixteen "luxury" vehicles were taken in one spate of thefts across Down and Armagh.
The head of the Garda's national stolen vehicle investigation unit, Detective Superintendent Michael Mullen, has appealed to motorists to be more careful.
He said a series of preventative measures could be taken to thwart the thieves.
Motorists should ensure their vehicles are locked when parked outside their homes.
If they have a garage, the vehicle should be parked there and the building locked. The motorists can also buy a blocking wallet, lined with metallic material, to help prevent the signal from being diverted from the key to the vehicle. Commonly known as a "Faraday pouch", it can be bought for as little as €5.
Alternatively, motorists can turn to an old-fashioned device, a steering column lock, which can prevent the thieves from driving away. They can be bought for between €50 and €60.
An investment in a GPS tracker device is seen as worthwhile by Det Supt Mullen, who says that the provision of CCTV cameras around the house will also act as a deterrent.
Motorists are also advised to keep all vehicle keys, including spare sets, well away from exterior doors and walls.
Research by 'What Car?' Magazine has found that some keyless models can be stolen within 10 seconds.
The technology, which allows motorists to unlock their car without pressing a button, is intended to work only when the fob is within two metres of the vehicle.
However, criminals have acquired technology which is capable of relaying a signal between the fob and the vehicle, even if the car is parked 100 metres away.
Motoring experts say two criminals working together are able to trick the technology, with one standing close to the home and the other near the vehicle, and using an amplifier to boost the signal.
Police in Canada have found that many of the newer Toyota and Lexus models being stolen there are destined for resale in Africa and the Middle East.