Motorists are being urged to come forward if they saw a theft from a car wash along the main route between Lynn and Downham earlier this month.
Police say two metal signs were stolen from the Autoshine hand car wash site on Lynn Road, Tottenhill, at around 8.20pm on Sunday, June 8.
Investigating officer, PC Cheryl Ironside, said that, although the incident was captured on CCTV, the identity of the person recorded in the image is not clear.
She added: “It happened next to the A10 and unfortunately the suspect’s car is parked out of sight of the camera.
“The road was busy at the time so I’d been keen to hear from anyone who may have witnessed the incident or noticed a car parked on the verge.”
Anyone with information about the incident should contact PC Ironside via the non-emergency 101 number.