Police are hunting yobs who hurled chunks of concrete from a footbridge in East Sussex onto motorists below in the middle of the night.
Two cars were damaged as they passed under the footbridge over King Offa Way in Bexhill-on-Sea at around 12.30am on Wednesday.
No-one was injured but a Renault Megane driven by a 27-year-old local woman sustained damage to its bonnet, windscreen and front bumper.
In the second incident, a Fiat Punto with a 48-year-old man behind the wheel and three passengers received damage to its windscreen and roof.
Sussex Police officers suspect the concrete came from a wrecked bird bath and have appealed to anyone who may have had one stolen recently to come forward.
A police spokesman said: "Thankfully no-one was injured but we have seen from similar cases elsewhere in the country the serious consequences which can occur as a result of incidents of this nature.
"We are appealing for anyone who saw any suspicious activity around the area of the bridge when this incident took place to contact Sussex Police or anyone who knows who may have carried out this act."
Anyone with information is asked to call Sussex Police on 101 or Crimestoppers anonymously on 0800 555 111.