Buckingham Palace has had several security breaches. The most serious breach came in March 1982 when Michael Fagan broke into the Queen’s bedroom at the palace. She woke to find him sitting on her bed.

And in 1981, Marcus Sarjeant, 17, fired six blank shots at the Queen at the Trooping the Colour ceremony. In 1990, Stephen Goulding was jailed for three months after breaking into palace grounds in 1990. He claimed he was Prince Andrew Windsor and declared the Queen was his “mum”.

In 1992, an intruder walked into St James’s Palace and downed a whisky in Princess Alexandra’s private apartment. And in 1994, a naked paraglider landed on the roof of Buckingham Palace. American James Miller was fined £200 and deported. In 1995, student John Gillard rammed the palace gates in his car at 80 kmph, tearing one off its hinges. In 2003, an undercover reporter from the Daily Mirror got a job as a footman at the palace.