Officers believe it may be linked to thefts from eight vehicles, which took place in the Bilton and Jennyfields areas.
Power tools were stolen when the vehicles when they were broken into between 12.30am and 1.10am yesterday (Tuesday).
A North Yorkshire Police spokesman said: "We are conducting enquiries and are requesting the public’s assistance to help bring the offenders to justice.
"In particular, we are appealing for information about a dark coloured vehicle, possibly a Land Rover, which was seen acting suspiciously in the area."
Vehicle owners, particularly trades people who carry their tools, are being urged to remove all valuables when they park up at night and to ensure their vehicles are locked when not in use.
Anyone with information is asked to email [email protected] or call 101, select option 2, and ask for Hayley Goodlad.
Alternatively, call the independent charity Crimestoppers in confidence on 0800 555 111.
Please quote the North Yorkshire Police reference number 12170139827.