Stornoway Primary School has suffered “extensive damage” after being broken into.
Police are appealing for information after a break-in at the school between December 23 and yesterday.
Entry was gained and extensive damage was caused to various areas of the building which is located on Jamieson Drive.
Sergeant Ross Masson of Stornoway Police Station said: “It is very disappointing that this mindless act of vandalism has taken place at Stornoway Primary School.
“There is a minority in our community who feel this sort of behaviour is acceptable, but I want to be clear that it is not.
“We are following all lines of inquiry to make sure that those responsible are found.
“I would urge anyone with information or who may have seen anything to come forward.”
Anyone with information should contact police on 101 quoting incident number 2527 of 2 January, or call Crimestoppers anonymously on 0800 555 111.