Police have released CCTV showing criminals using relay boxes to steal a car without needing the key.
It is believed to be the first time a 'relay crime' has been captured on camera, West Midlands Police said.
The video shows two men pulling up outside a house with a Mercedes on the drive.
They use relay boxes to receive a signal from the key inside the house tricking the car's system to unlock the doors and start the ignition.
It takes them under one minute to make off with the stolen vehicle.
The vehicle, which was stolen in Solihull on September 24, has not been recovered.
Relay boxes are capable of receiving signals through walls, doors and windows but not metal.
Mark Silvester, from West Midlands Police, said: "To protect against this type of theft, owners can use an additional tested and Thatcham-approved steering lock to cover the entire steering wheel.
"We also recommend Thatcham-approved tracking solutions fitted to the vehicle.
"It is always worth speaking to your main dealer, to ensure that your car has had all the latest software updates and talk through security concerns with them."
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