Police are investigating the unauthorised excavation of an Iron Age structure in the outer Hebrides.

Officers are liaising with Historic Environment Scotland (HES) after tumbled stone was cleared from Dun Torcuill, a site on an uninhabited island on a North Uist loch.

The damage to the monument, which is legally protected and recognised as of national importance, is being treated as a criminal offence.

The incident was reported to police on Tuesday, October 22.

Sergeant Gavin McDevitt has urged anyone with information to get in touch.

He 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.

"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."