Police are appealing for information after two cars were damaged when a corrosive substance was thrown over them.
A blue Ford Focus and a black Rover MG, both owned by the same person, were targeted in Crook overnight on Friday.
The Ford was in Stanhope Terrace and the MG was in George Terrace.
Police were alerted by a George Terrace resident in the early hours of Saturday morning (May 2).
PC Tony Elliott said two youths described as being about 15 and wearing dark hooded clothing were spotted in George Terrace, which is opposite the fire station, at about 1.30am.
They are believed to be involved in the attack on the Rover and were seen running off in the direction of Bladeside.
He said: "I would urge anyone with information relating to the attacks on either of these cars to come forward."
PC Elliott can be contacted at Crook police via the non-emergency number 0345-60-60-365 or Crimestoppers on 0800-555-111.
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