A car is being broken into every two days in Colchester according to latest figures.
Essex Police are asking people to make sure their cars are locked and that valuables are kept out of sight.
In January and February, 14 vehicles were broken into each month with most thefts happening in the afternoons, evening and overnight, in The Hythe, town centre and Christchurch New Town areas of Colchester.
Neighbourhood policing officers have stepped up patrols, and undercover officers are also being used to try and catch the thieves red handed.
Insp Barry Atkinson said: "We are asking people to ‘think outside the box’ and remove mobile telephone and sat - nav cradles and brackets from dashboards, thereby leaving no clues for opportunistic thieves.
"Identification is crucial during our investigations as they not only link items to offences, but also reunite items with their rightful owners. People should record car stereo serial numbers and postcode their possessions using ultra-violet pens.”
Drivers are also being asked not to leave their cars unattended while defrosting them in the mornings.
Anyone with information is asked to call police on 101.