Detectives are investigating a new surge in the number of “keyless” luxury car thefts in London’s most exclusive areas.

Hundreds of top of the range cars including Range Rovers, BMWs and Audis are being taken by gangs using a hand-held high tech device that bypasses security systems.

In one street alone in Chelsea, four luxury vehicles, including three Range Rovers, have been stolen in recent weeks, according to residents.

The theft of one £85,000 car was caught on CCTV with images showing the criminal casually clicking open the lock systems before climbing inside and driving slowly away.

In one case, a car stolen from Ormonde Gate near the Chelsea Royal Hospital, activated its internal tracking system and was traced to a scrapyard in Kingston.

Another victim in the street received a replacement car through their insurers - only to have it stolen a week later.

In the latest incident, property developer Laura van Bilderbeek, 38, had her top of the range BMW estate stolen from outside her new home on Ormonde Gate on Sunday.

She said: “I am really upset, the BMW was used to ferry the family around and it is a real blow. The manufacturers should make it more difficult to steal their vehicles. As it is they can steal them in seconds.

“My new flat was also broken into the week before - it has been a stressful start to my life there.”

It is believed the thieves are targeting vehicles with “keyless” ignition systems bypassing security with a hand-held device that can be bought on eBay for as little as £50.

They are then dismantling them to remove the vehicles’ electronic tracking devices and shipping them to eastern Europe.

Met figures show that car thefts in the borough of Kensington & Chelsea are now rising faster than any other borough.

Figures from Thatcham Research, the motor insurers’ research centre, show that between January and July 2014 almost 300 Range Rover Evoques and Range Rover Sports were stolen in London, along with 63 BMW X5s and Series 3 models.

A spokesman said all top of the range cars were vulnerable to keyless thefts, it simply depended which make was on the thieves’ latest “shopping lists.”

Last month it was claimed that high end insurers were refusing to insure new Range Rovers because of the numbers being stolen.

Local police also warned car owners to use old-fashioned steering-wheel locks to protect high-tech vehicles.

The CCTV shows a thief breaking into a new grey Land Rover Sport at 10.45pm on December 2.

The man walks slowly up to the vehicle with his hands in his pockets and and clicks the remote control lock, causing the frontlights and indicators to flash as the doors to open.

He then steps inside, appears to check if keys have been left in the sun visor, and takes just over 50 seconds to bypass the ignition security before driving away at around 5mph.

The victim of the theft, who was away in France at the time, told the Standard: “I am still extremely upset and I still want my car back. It’s a 2014 plate, it’s still new.

“If you watch the CCTV footage the man casually gets in the car and drives away so slowly, he’s driving the car slower than I do coming out of a parking space.

“I’ve been living in London for 20 years and this is the first time anything like this has happened.”

Another Range Rover owner said: “I’ve had to put a huge yellow clamp on my steering wheel to prevent it being stolen. I look out the window numerous times throughout the night because I am so worried that it’ll be next.”

A spokesman for Jaguar Land Rover, which makes Range Rovers, said the company was introducing a new security measure to tackle the problem.

He said: “This is an extremely serious issue for the automotive industry. At Jaguar Land Rover, we have been working closely with the Metropolitan Police and other forces across the country and this has resulted in a number of prosecutions.

“We have a dedicated engineering team continuously developing new technologies to try to stay one step ahead of criminal gangs. So far, three security upgrades have already been implemented this year alone. We are now introducing our fourth upgrade, which we are confident, will address the latest theft mechanisms being used. “