Police detain man after 'shotgun cartridges' thrown into Buckingham Palace

Police in London on Tuesday arrested a man allegedly armed with a knife and accused of throwing suspected shotgun cartridges into the grounds of Buckingham Palace.

The arrest, at about 7:00 pm (1800 GMT), comes just days before King Charles III's coronation, which will be attended by global royalty and world leaders amid a massive security operation.

The Metropolitan Police said officers also conducted a controlled explosion on a suspicious bag the man was carrying "as a precaution". It later added that it was not treating the matter as terrorism-related at this time.

The man has been arrested on suspicion of possession of an offensive weapon after he was searched and a knife was found, the London force said in an update some three hours after the incident.

"Officers worked immediately to detain the man and he has been taken into police custody," Met Police chief superintendent Joseph McDonald said in a statement.

"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."

British media reported that neither Charles, 74, or his wife Queen Consort Camilla, 75, were at the palace at the time.

Buckingham Palace officials declined to comment.

The drama unfolded Tuesday evening after the man approached the gates to the palace and threw several items into the grounds suspected to be shotgun cartridges, according to the Met.

They have been recovered and will be taken for specialist examination.

The Mall, leading to Buckingham Palace, has been closed off to traffic in preparation for Saturday's coronation, which is the first to take place in Britain for 70 years.

Thousands of ceremonial troops will take part in a procession from Buckingham Palace to Westminster Abbey as part of the coronation, with huge crowds expected.

The security operation to protect the route to and from the abbey -- dubbed Operation Golden Orb -- is one of the biggest in recent years.

It will include rooftop snipers and undercover officers, as well as airport-style scanners, sniffer dogs and a no-fly zone over central London.