Detectives are urging owners of cars with keyless entry systems in Warrington, Runcorn and Widnes to be vigilant following a spate of thefts of these vehicles.
Criminals are taking advantage of vulnerabilities in these systems which enable them to drive cars away without first having to break into homes to steal keys.
Over the past six weeks seven cars with keyless entry systems have been stolen in Warrington and six have been stolen in Halton, with high performance Ford cars particularly being targeted.
Detectives are concerned by the recent spike in keyless car thefts and are appealing for residents to take action to reduce their chances of becoming victims.
Detective Sergeant Tom Hall said: “Keyless entry systems on cars offer convenience to drivers but they can, in some situations, be exploited by car thieves.
“There has been a worrying recent rise in keyless car thefts in Warrington, Runcorn and Widnes, with criminals cloning keys that are inside homes by sending signals to them from outside overnight.
“We are doing all we can to tackle the issue but we need residents’ help to drive down this type of crime.
“By assessing your current security measures and taking a few simple steps you can significantly reduce the chances of your car being stolen.
“Think about how you store your keys at home. Keeping your keyless entry fob out of sight is not enough as thieves only need to get near to the key to be able to clone it.
“I urge drivers to keep both sets of keys in a Faraday bag. They block the signal from the fob and are widely available.
“Additional security devices such as mechanical steering locks and trackers are also effective in protecting vehicles from thieves.”