Police want to know who was transporting Manx rock on the Ramsey Road in Laxey after a large piece shattered the driver's side window of a car.
A black Renault Megane was parked near Minorca crossroads when the incident occurred between 2pm and 4pm on Friday.
A police spokesman said: 'Evidence found at the scene suggests that a large piece of Manx rock has fallen from a passing vehicle and smashed through the window of the Megane.'
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