Police are warning Ford Transit owners to never leave valuables in their vans after receiving reports of break-ins.
Clay Cross Police Safer Neighbourhood Team has said thieves may have found way to bypass locks on the van.
Since the start of April, there have been more than 10 reports of break-ins and thefts of this type of van in North East Derbyshire.
On each occasion no damage was done and it is believed offenders may be using a device to bypass the lock system.
A police spokesman said: "We are working hard to investigate these offences and find those responsible. We’d also advise people to never keep tools or valuables in your vehicle overnight and to consider fitting additional security such as a deadlock or an alarm."