AN old Second World War building near Edinburgh that has been sprayed with a Saltire flag is to be investigated by Historic Environment Scotland.

Pictures of the building – one of several built on Cramond Island in the Firth of Forth to fortify Edinburgh against submarine attacks during WW2 – were shared on social media, with some expressing outrage and calling it "vandalism".

The Saltire was depicted with a yellow heart at its centre.

Historian Dr Gordon Barclay claimed it was a criminal offence in response to a post from anonymous Unionist agitator "Agent P", who claimed the "eyesore can be seen from two miles away".

Barclay wrote: “A criminal offence under the terms of the Ancient Monuments and Archaeological Areas Act 1979. The WW1 and WW2 defences are a nationally important scheduled monument.”

Not everyone was in agreement, however. One X user wrote: “How is a Saltire an eyesore to you? Politics aside, do you not like Scotland?”

When approached, Historic Environment Scotland (HES) – the lead public body established to investigate and care for Scotland's historic environment – told The National that they were “investigating” the incident.

They said: “We have been notified about this incident and are now investigating.”

The assortment of buildings are a “scheduled monument” according to the HES website, and are of “national importance”.

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The website reads: “This monument is of national importance because it is an integral part of the network of defences constructed in the First and Second World Wars to defend the Lothian coast and strategic interests in Forth.

“The diverse and well-preserved collection of First and Second World War structures on Cramond Island include unusual features such as the triple group of searchlight emplacements and a unique anti-shipping barrier.”

The island is part of the Dalmeny Estate, owned by the Rosebery Estates Partnership – who have been approached for comment.

While Edinburgh City Council do not own the land, Scottish Labour councillor Val Walker – also the culture and communities convener – did comment, saying: “It is a shame to see vandalism anywhere in our city, but especially of a ‘scheduled monument’ as is the case of the war defences on Cramond Island.

“I hope that these defences can be restored properly as they are an important part of our region’s history.”