The driver caught steering with his feet while sat on the roof of his car was an 18-year-old Dereham man.
Police were called to Halfords on Yaxham Road at 1.15pm on Saturday after reports of a black VW Polo being driven by a man dangling his legs through the sunroof.
The car was in-gear and was being driven around the car park. It is thought the man started the car and then jumped on to the roof.
Officers fined the young driver £100, gave him three points on his licence and issued with a warning which lasts 12 months and could result in his car being seized if the incident happens again.
A spokesman for Norfolk Police said the car park is a public place therefore the incident can be classed as a road traffic offence.
The shop sits on an estate with a pet and bike shop and a car dealership
Did you see this happen? Did you take a picture? Email rosa.mcmahon@archant.co.uk
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