A man has been arrested after climbing Buckingham Palace’s front gates in the early hours of the morning.
The 22-year-old was held on suspicion of trespass at around 2am on Wednesday morning by specialist royal police officers, the Metropolitan Police said.
The Queen was in residence at the time, a palace spokeswoman said.
She declined to say whether the Queen had been informed of the incident.
The intruder was not carrying any weapons and the incident is not being treated as terror-related, according to Scotland Yard.
According to The Sun the intruder, who tried to get inside the palace, was on the loose in the grounds for around four minutes before he was apprehended.
At their lowest point the gates are several metres high and stand well above head height.
The man remains in custody at a nearby police station in central London.
A Metropolitan Police spokeswoman said: “The 22-year-old man was arrested at approximately 2am on Wednesday July 10 by officers from the Met’s Royalty and Specialist Protection Command after he climbed over the front gates at Buckingham Palace.”
The force declined to say whether there would be a review of security after the incident.
Later on Wednesday the Queen awarded jazz musician Gary Crosby the Queen’s Medal for Music.
The 64-year-old double-bassist accepted the award in person at a special audience with the Queen.
Last year a homeless man who trespassed in the grounds of Buckingham Palace and damaged items before sleeping on them was jailed for 28 days.
Steven Lawlor entered the protected royal site on July 16 and broke poster boards and glass cabinets fixed to metal railings to use as bedding, Westminster Magistrates’ Court heard the following month.
Security officials found the 44-year-old sleeping on the ruined items in an area near the south-east corner of the palace just after 5am, where he bedded down at around 1am, the court was told.
In September 2013 a security review was launched after an intruder was able to scale a fence and get inside the palace, before being arrested by police.
No members of the royal family were at the palace at the time, and the man, who was found shortly before 10.30pm “in an area currently open to the public during the day”, was arrested for burglary, trespass and criminal damage.
A second man was arrested outside the palace for conspiracy to commit burglary.
Two days later the Metropolitan Police apologised to the Duke of York after officers challenged him in the gardens of Buckingham Palace at around 6pm.
Prince Andrew said: “The police have a difficult job to do balancing security for the Royal Family and deterring intruders, and sometimes they get it wrong.
“I am grateful for their apology and look forward to a safe walk in the garden in the future.”
The break-in was one of the most serious security breaches at the palace since 1982, when Michael Fagan evaded guards to get inside the Queen’s private chambers while she was still in bed.
The unemployed father-of-four, 31, spent around 10 minutes talking to the Queen after he climbed over the palace walls and up a drainpipe.
The Queen managed to raise the alarm when Fagan asked for a cigarette, allowing her to call for a footman who held him until police arrived.