Police are appealing for witnesses to the incident which happened in Theatre Street between 12.30pm and 3.15pm on April 5.
The victim parked their blue and green Hyundai Bayon in a disabled bay and when they came back to the car they found a large dent on the bonnet.
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Two smaller dents were also discovered on the vehicle.
Anyone who witnessed the incident is asked to contact Norfolk Constaulary quoting crime reference 36/22856/24.
Police are appealing for witnesses to the incident which happened in Theatre Street between 12.30pm and 3.15pm on April 5.
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