Police are given advice on how to foil keyless car thieves after several instances of cars being stolen from just outside houses.

Thames Valley Police said the offence normally involves keyless cars and normally happens overnight.

However in some cases this has happened in the middle of the day when no-one expects it.

Keyless ignition systems come with a fob that transmits a unique low-frequency signal to the car's computer system, which then allows you to push a button on the dashboard or console to unlock the doors and start the engine.

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Hackers can take advantage of this by using a cheap relay box to copy and transmit the signal from your key fob while it's still inside your home or on your person, making it easy to steal your vehicle.

This is called a relay attack, and it's simple for thieves to pull off as long as they have a friend.

The police say the best way to protect against this theft is to buy a signal-blocking RFID key fob pouch or box for your keys.

Professional thieves will also de-activate any tracking signals from the vehicles as they are very organised and know what they are doing, police warned.