A man and woman were taken to hospital after a concrete slab was launched at a taxi from a pedestrian flyover.
The incident took place on the B921 as the taxi headed towards Kinglassie, Fife, at about 12.30am on Sunday.
The man and woman, both 37, were taken to Glenrothes Hospital for treatment.
Glenrothes police have appealed for witnesses.
It follows two similar incidents at the same pedestrian flyover where two vehicles were hit by wheelie bins from above.
The first incident took place on Sunday July 16 at about 1am and the second took place at about 3.55am on Wednesday July 19.
No-one was injured in these incidents but both cars were damaged.
Inspector Kirk Donnelly of Glenrothes Police Station, said: “Two people have suffered injuries as a result of these reckless actions and there could easily have been far more serious consequences.
“I would therefore appeal to anyone who witnessed any of the incidents or has any information that might assist with our inquiries to contact us on 101, quoting reference 0108 of August 6, or call Crimestoppers anonymously on 0800 555 111.”
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