Police have launched a probe into reports of an unauthorised excavation of an Iron Age site in the Western Isles.

Officers are investigating allegations stones have been removed from a protected stone built tower on the uninhabited island of Dun Torcuill in North Uist.

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Authorities are liaising with heritage body Historic Environment Scotland (HES) over claims the tower - known as a ‘broch’ - was damaged in the incident, thought to have taken place in late October.

They are now appealing for witnesses and have asked anyone with any information to come forward. 

Dun Torcuill is legally protected as a site of historic importance and was once considered one of the best preserved examples of the monuments in the country.

Dozens of Brochs are scattered around Scotland, most in the Westerm Isles and Highlands.

Sergeant Gavin McDevitt of Lochmaddy Police Station said: "Damaging or removing any part of a scheduled monument is a criminal offence. In this instance, there is the potential for destabilisation of the monument, and or the loss of archaeological deposits previously protected by the tumbled stone.”

"It is an offence under the Ancient Monuments and Archaeological Areas Act 1979 to undertake works without Scheduled Monument Consent. 

“The penalties for offences under the Act are considerably higher than those for damage to property or vandalism offences, with fines ranging up to £50,000 or prison sentences of up to two years.”

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He added: "Police Scotland and HES are working closely to investigate this report and we are particularly keen to hear from anyone who has visited the monument within the last six months.”

"If anyone has any information that could help, please call 101 and quote the Police Scotland reference number 1652 of October 22."