Historic Environment Scotland (HES) said there was some damage caused to the protective glass housing the stone.

The Crown Room and Royal Apartments at the castle were closed following the incident, which happened shortly before 11am on Wednesday in the Crown Room.

This is Rigged protest group said the incident echoed the history of the Stone of Destiny, which was repatriated from Westminster Abbey to Scotland by a group of University of Glasgow students 700 years after the stone was stolen in the Wars of Independence.

Police Scotland said two women, aged 20 and 24, and a 20-year-old man were arrested in connection with the incident.

This is Rigged issued two demands - that supermarkets reduce the price of baby products by a quarter, and that the Scottish government fully funds a community food hub per every 500 households, providing three meals a day to anyone who needs them.

In a statement, the group said: "Food is a human right. Hunger is a political choice. The times we live in are defined by crisis, by instability, by greed."

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A HES spokesperson said there was a "small disturbance" in the Crown Room and police were called to the scene.

The spokesperson added: "There has been some damage to the protective glass housing the honours, however the casing was not breached and the honours themselves were not damaged.

"The castle remains open, however we have temporarily closed the Crown Room and Royal Apartments."

A Police Scotland spokesperson said: "Around 10.45am on Wednesday, we were called to a report of a small protest within Edinburgh Castle.

"Officers attended and two women aged 20 and 24 and a 20-year-old man were arrested in connection with damage caused. Inquiries are ongoing."