Around 10 cars were damaged in the Redmanville and Corcrain areas of Portadown in a spate of overnight attacks.
The vandalism took place late on Sunday evening and the early hours of Monday morning, with estates targeted including The Oaks, Corcrain Drive and Dawson Green.
Police said it appeared that a stone or key had been used and numerous panels had been damaged.
They said, “A lot of the owners are elderly, vulnerable and entirely undeserving of such callous and selfish acts of thuggery against them.”
Councillor Darryn Causby has condemned the “disgraceful attack”.
He said, “People work hard to pay for their cars and no doubt rely on them for their daily routine and for someone to damage them in this way is a total outrage.
“At this stage there doesn’t appear to be rhyme or reason for this attack on the community and it beggars belief that someone would be so spiteful towards our residents.”
He appealed to police to step up patrols and for anyone with information to contact police. The number is 101.