A man has been arrested outside Buckingham Palace after throwing suspected shotgun cartridges into the palace grounds, police said.

The Metropolitan Police said he was detained at around 7pm on Tuesday after he approached the palace’s gates in central London and threw a number of items.

He was held on suspicion of possession of an offensive weapon after he was searched and a knife was found, but he was not carrying a gun.

Cordons were put in place after he was found with a “suspicious bag” but have since been removed, the force added.

A controlled explosion was conducted as a precaution, Scotland Yard said.

The Herald: The scene outside Buckingham PalaceThe scene outside Buckingham Palace (Image: PA)

Neither the King nor the Queen Consort were at Buckingham Palace at the time of the incident.

But Charles did host Australian Prime Minister Anthony Albanese during an audience at the palace earlier on Tuesday.

The items thrown into the palace grounds “have been recovered and will be taken for specialist examination”, the Met said.

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Police say they are not currently treating the incident as terror-related.

It is understood it is being treated as an isolated mental health incident.

Chief Superintendent Joseph McDonald said: “Officers worked immediately to detain the man and he has been taken into police custody.

“There have been no reports of any shots fired, or any injuries to officers or members of the public.

“Officers remain at the scene and further inquiries are ongoing.”