By Brad Segall

RADNOR, Pa. (CBS) — Police in Radnor, Delaware County, say they want to catch whoever is responsible for throwing rocks at cars from an overpass — before someone gets seriously injured.

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Authorities say there have been six incidents since Christmas. Rocks are being thrown at cars on West Wayne Avenue from the Radnor Trail.

Police believe they are looking for teenagers because most of the incidents have occurred on weekends, and two of the victims say they saw some teens running from the scene.

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“Now, they may think this is a harmless prank, but this can cause extensive damage and even cause fatalities,” says Radnor police superintendent William Colarulo. “And this is something that we have a zero tolerance for.”

Miraculously, Colarulo says, there haven’t been any physical injuries from the rock-throwing incidents, just damage to windshields and the bodies of the cars.

But Colarulo adds that he’s worried about drivers losing control of their cars if they are hit by the flying objects.

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