POLICE are warning car owners about the dangers of 'key hacking' following several suspicious incidents.

Key hacking is when thieves attack built-in systems that can unlock a car when the key is nearby, without having to press a button on the fob or put a key in the lock.

If close to the car, the key sends a short-range signal that tells it to unlock, even if it's in your handbag, pocket or short distance away.

Car thieves have devised ways to scan for and hack the signal to give them access to some cars.

A spokesman for Dorchester Police said: "Dorchester NPT are aware of some recent victims of thefts from motor vehicles whose cars have been found unlocked with no damage to them.

"Although we cannot prove that key hacking has taken place the following tips may be useful."

The RAC has issued the following advice:

* Take preventative measures to stop someone from stealing your key fob signal.

Car key signal blockers are metal-lined key wallets or special bags designed to keep your keys safe, also known as Faraday bags.

They’re relatively inexpensive at around £5 upwards, but not all are of the same quality

Be sure to test the bag once you've bought it to make sure it works, by holding it close to the car with the key in and checking whether or not it opens.

Make sure you put the keys in the bag as soon as you have locked the car, and don't forget to use one for your spare car key in the house. If you get one large enough, you can also pop your mobile in it which blocks the signal so you won't be distracted by your phone while you are driving.

Do your research to find the right product for you. Also, make sure you know how to use the bag, some may have more than one pouch, but only one is the specially lined pouch.

*Make sure all software has been updated on your vehicle

*Use steering locks and other preventative measures that will put thieves off attempting to drive off with your car

RAC Insurance director Mark Godfrey says: “Drivers with keyless systems can take precautions to prevent their vehicles being stolen including storing their keys in protective cases so the signal can’t be cloned, or even switching off the keyless feature on the fob if it is an option.

“And try to avoid storing your keys by the front door – it may not be fail-safe but get into the habit of leaving your keys well away from your vehicle, such as at the back of the house.”