A man “asked to speak to a soldier” outside Buckingham Palace before launching shotgun cartridges into the grounds, police have said.
The suspect approached the gates of the royal residence shortly after 7pm on Tuesday evening, amid a heavy police presence in the lead-up to the King’s coronation.
Metropolitan Police deputy assistant commissioner Ade Adelekan said he spoke to a police officer on guard and “asked to speak to a soldier”.
“They said that wasn’t possible, at which point he threw some shotgun cartridges over the gates,” he added.
“They grabbed him in seconds, he was detained, he was searched and he was found to be in possession of a lock-knife.”
Mr Adelekan said that while being arrested, the man raised officers’ suspicions about his backpack by telling them it “needed to be handled correctly”.
The bag was destroyed in a controlled explosion, but police have not confirmed what was inside, or finished analysis of the shotgun cartridges.
The suspect remains in custody, after being arrested for possession of ammunition and the knife.
Mr Adelekan said the incident was not being considered as terror-related at this stage, and a mental health incident had been carried out.
He had no knowledge of reported previous incidents where the same man allegedly said he wanted to kill the King, and that he made no mention of the King on Tuesday.
The incident came amid an increased police presence around Buckingham Palace and other major London sites for rehearsals ahead of Saturday’s coronation.
Hundreds of thousands of people are flooding into London to celebrate, while protests are also expected to take place.
The security services are working to stem any threat from jihadists, neo-Nazis and other extremists who revile the royal family as a symbol of the British state, while police are also monitoring “fixated” individuals.
Recent years have seen several terror cases and threats aimed at the royal family, including specifically targeting the late Queen and Prince Harry.
In February, a man admitted taking a loaded crossbow to Windsor Castle and threatening to kill the Queen while dressed “like something out of a vigilante movie”.
Jaswant Singh Chail was caught in the private grounds of the royal residence on Christmas Day in 2021 and “informed officers at the scene that he intended to kill the Queen”.
He pleaded guilty to a rare charge under the Treason Act 1842 over the incident, which Chail said was revenge for a 1919 massacre by British colonial troops in India.
Chail was detained under the Mental Health Act and has not yet been sentenced.
In August 2017, an Isis-inspired terrorist attempted an attack on police officers outside Buckingham Palace, slashing them with a sword while shouting “Allahu akbar”.
Mohiussunnath Chowdhury originally planned to target soldiers at Windsor Castle but changed his plan after an apparent sat-nav error.
He was initially acquitted of terror charges over the attack, but was later jailed for mounting another plot after being freed from prison.
