Four people have been arrested after custard and apple crumble were flung at a display case containing part of the Crown Jewels in the Tower of London.

Police were called shortly before 10:00 GMT on Saturday after the case containing the Imperial State Crown – which is typically worn by the King at formal ceremonies – was defaced.

The Metropolitan Police said four people had been arrested on suspicion of criminal damage. The Tower’s Jewel House was temporarily closed to the public while the police investigated.

Take Back Power – which appears to be an offshoot of Just Stop Oil and which describes itself as a new non-violent civil resistance group – has claimed it was behind the incident.

The group said it carried out the stunt to demand the UK government establishes a permanent citizen’s assembly, or “House of the People”, with the power to “tax extreme wealth and fix Britain”.

Policing minister Sarah Jones said that the incident was “disgraceful”, adding: “There is a clear difference between the democratic right to protest and unacceptable behaviour.”

Footage shared by Take Back Power on social media showed one protester removing a large foil tray of crumble from a bag before slamming it against the glass protecting the Imperial State Crown.

Another then poured a tub of bright yellow custard on the front of the case.

“Democracy has crumbled,” one protester could be heard shouting. Another added: “Britain is broken. We’ve come here to the jewels of the nation to take back power.”

Meanwhile, surprised tourists could be seen reacting to the stunt.

Historic Royal Palaces confirmed that the Imperial State Crown was not damaged.

The Jewel House reopened to the public early in the afternoon.

This is the second demonstration claimed by the group in the past few days.

On Wednesday, three protesters emptied bags of manure onto the floor of the Ritz hotel lobby under its 25ft Christmas tree.

Take Back Power has emerged in recent weeks on social media channels used by Just Stop Oil activists. The environmental protest group refers to Take Back Power as a “new project”.

Just Stop Oil – responsible for a number of high-profile protests including throwing soup on Vincent van Gogh’s Sunflowers and climbing onto motorway gantries – announced it was ending its use of direct action in March.

The Imperial State Crown is a famous symbol of the monarchy and was worn by King Charles III as he left Westminster Abbey on his coronation day in 2023.

Beyond coronations, the priceless working crown is only used during formal occasions, such as the State Opening of Parliament.

When it is not being used, it is kept in the Jewel House at the Tower of London.

It was originally made in 1937 for the coronation of King George VI and contains 2,868 diamonds, 17 sapphires, 11 emeralds, four rubies and 269 pearls and weighs over a kilogram. (BBC)

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