King Charles and Queen Camilla received news of a breach in security on Tuesday – days before they will be crowned at Westminster Abbey.
A man was detained by police at around 7pm after he approached the Palace's gates in central London and threw a number of items, the Metropolitan Police said.
He is being held on suspicion of possession of an offensive weapon after a knife was found, the force said. Suspected shotgun cartridges were also thrown into the grounds of Buckingham Palace.
© Getty ImagesPolice carried out a precautionary controlled explosion which could be heard live on GB News, while cordons were put up in the area.
Scotland Yard say they are not treating the incident as terror-related and it is understood it is being treated as an isolated mental health incident.
Thankfully, the royal couple were not in residence at the time of the incident.
© Getty ImagesFurthermore, they are not letting it detract from the excitement of the coming days.
On Wednesday, a new post was shared on the royal couple's official Instagram page. It showed members of the military taking part in an evening rehearsal ahead of the coronation.
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The caption read: "Three days to go… #Coronation."
It comes after Buckingham Palace shared details of the royals who will take part in Big Lunch and Big Help Out events as part of the coronation weekend from 6 to 8 May.
The Duke and Duchess of Edinburgh will be among the royals getting involved in the festivities taking place across the nation, with thousands of people expected to come together for street parties on Sunday.
© Photo: Getty ImagesPrince Edward and Sophie, who became the Duke and Duchess of Edinburgh in March, will attend a big lunch in Cranleigh.
Meanwhile, the Princess Royal and her husband, Vice Admiral Sir Tim Laurence, will attend a community street party in Swindon, while the King's nieces, Princess Beatrice and Princess Eugenie will attend a big lunch in Windsor.
© Getty ImagesMembers of the royal family will then attend the coronation concert at Windsor Castle on Sunday evening, with Take That, Katy Perry and Lionel Richie among the star-studded line-up.
Kensington Palace is expected to release information about the Prince and Princess of Wales's plans over the weekend in due course.
Buckingham Palace said the Big Help Out on Monday will "highlight the positive impact volunteering has on communities across the nation".
