As criminals become increasingly sophisticated in how they target hi-tech vehicles, how can you keep your car safe

The ringleaders of a gang of thieves are behind bars after using keyless entry technology to steal dozens of cars while their owners were asleep.

The "highly sophisticated" criminal group utilised a combination of signal boosters and signal jammers to access a range of vehicles, including Range Rovers, vans, and motorcycles - many of which were parked on driveways at the time.

They were then driven to so-called chop-shops, where they were disassembled for parts and sold on.

Over the space of just eight months, vehicles worth more than £2 million are believed to have been taken, some of which also contained thousands of pounds worth of tools.

The case raises fresh questions about the security of modern cars and what owners should do to keep their vehicles safe.

Here, Yahoo News UK looks at what the latest technology can do and how you can make sure your vehicle is secure.

First introduced as early as the 1980s, keyless entry uses a signal transmitted by a key fob to allow a driver to lock or unlock their car just by walking to or from it.

If you have to push a button to access your vehicle, it's not keyless entry.

Early systems used radio waves, which made them vulnerable to hackers, and while these security concerns have been largely rectified, new vulnerabilities are found as quickly as the technology evolves.

And as thieves only need to be within a few metres of your car key to capture the signal, even if it appears to be safe inside your home, they can still gain access, start, and steal your car.

According to the Master Locksmiths' Association (MLA), "keyless car theft can take only 20-30 seconds".

Car thefts in the UK are at a 15-year high, with up to 70% of those taken thought to be keyless.

This usually involves a pair of thieves targeting a vehicle parked near the owner's home.

The first 'captures' the key fob's signal from inside the house and then uses a wireless transmitter to relay it to an accomplice positioned close to the target car to trigger the automatic unlock.

A device is used to remotely block the automatic locking signal from the fob while the car's owner walks away, leaving it an easy target for a thief.

Mainly an issue for drivers who use an app or 'digital key' for their cars.

If a thief steals the owner's phone or is able to otherwise hack into the device or relevant app, they may be able to gain entry to the car.

This can also be an issue for cars with external diagnostic ports.

In some situations, a keyless entry fob may be left close enough to a car that the automatic locking feature does not engage.

Even if the car will not start without the fob inside, this can still present an opportunity for opportunistic thieves to get inside and steal valuables.

While technology continues to march on, sometimes the old ways are the best as far as criminals are concerned.

Criminals will still try to fish them out of your home through your letterbox or open window with a hook on a stick, so try and avoid keeping them too close to your front door.

And wherever you are, try to keep them out of sight so it's harder for would-be thieves to snatch or clone them.

While your car's fob is supposed to automatically lock it as soon as you walk away, things can still go wrong.

Parts can fail and batteries can die, which could mean your doors remain open to anyone who wants to try the handle.

Criminals can also use signal blockers to stop the fob working.

Always manually check your vehicle has locked before walking away from it.

Modern vehicles often have diagnostic ports for engineers to run tests and checks, but which can also be used to unlock and start your vehicle.

If your car has a port like this, consider fitting a lockable cover.

Also known as a Faraday Bag, these containers are lined with layers of metallic material which stop the signals from the fob which tell the car to lock or unlock itself.

This can stop thieves using signal relays or boosters to artificially extend the range of the fob so they can get inside your vehicle.

Some manufacturers include a feature which allows you to turn off the wireless signals sent out by your car's fob.

This can stop 'relay theft', where thieves use signal relays or boosters to get into cars.

A steering wheel lock can still be pretty effective in putting off thieves unprepared to deal with one.

According to the MLA: "Most modern car thieves are equipped with laptops rather than hand tools, so mechanical devices - such as steering wheel locks - can be a real deterrent."

Although this won't actually stop a thief getting inside your car, it may make them less interested in trying to do so in the first place.

Having the last seven digits of your Vehicle Identity Number (or registration) engraved into windows, headlights and mirrors can make it much more difficult for criminals to sell it on after they've taken it.

If you buy a second-hand car, there is always a risk you may not have been given all the spare sets of keys.

Reprogramming can be expensive, but it does reduce the risk of a previous owner being able to take it.