Louts targeted a primary school and vandalised toys and safety equipment.
The damage was caused in the playground of Lincluden Primary between Sunday night and Monday morning.
Toys and gardening equipment were strewn around the grounds and a box used by the fire service in the case of a blaze was smashed. The police have appealed for information and say CCTV is being reviewed.
Education committee chairman Jeff Leaver called the attack “utterly unacceptable”.
Mr Leaver said: “It’s really pathetic, isn’t it? I wonder if it’s linked to the fire at the park on Lochside Road. In the first week of the school holidays it doesn’t bode well. I think this kind of thing is absolutely dreadful.
“These toys and bits of equipment are important parts of a young person’s learning. To see this kind of mindless trashing is utterly unacceptable. Damaging things that are used by the fire service also puts people in danger.
“I would like to remind parents and guardians to speak to their children about where they’re going and what they’re doing during the school holidays.”
North West Dumfries councillor David McKie said: “If people don’t want to go to the police with information they can contact me and I will go to the police. We can’t have this.”
A post about the damage on the police Facebook page received hundreds of comments and shares.
One said: “It’s actually shocking the amount of vandals that are about and can’t treat stuff with respect.”
A police statement said: “The damage was caused overnight on June 27 into June 28. CCTV is being reviewed. If you have any information about who was responsible please contact Dumfries Community Policing Unit on 101.”
