Thames Valley Police is appealing for witnesses after offenders broke in to cars in Banbury.
Between 8pm on Tuesday and 8am on Wednesday, offenders gained entry to six cars which were parked in Newcombe Close, Sussex Drive, West Bar Street, Fairfax Close, Portway and Woodgreen Avenue.
Offenders stole cash, satellite navigation systems, stereos and registration plates from some of the cars.
PC Henry Gillingham, from Witney Local CID, said: “These incidents are a reminder to all residents to lock their vehicles when they are parked. Although you may feel your area is safe, opportunist thieves are always around.
“Please remember to not leave loose change, devices or valuables out on display in your cars.
“If you have any information regarding the incident or saw anything suspicious in the areas please contact me through the 24-hour non emergency enquiry centre on 101.”
If you don’t want to speak directly to police you can contact Crimestoppers anonymously on 0800 555 111.