British police have arrested two men after a break-in at Buckingham Palace this week, one of the most serious security breaches at Queen Elizabeth's London residence in about 30 years.
A police spokesman said one man was found in the palace in an area that is open to the public at about 10.30pm on Monday.
He had scaled a fence to gain entry to the palace grounds.
He was arrested for burglary, trespass and criminal damage, while a second man was arrested outside the palace on suspicion of conspiracy to commit burglary. Both men were released on bail.
"No members of the royal family were at Buckingham Palace at the time of the incident," the police spokesman said. "A review of the specific circumstances of this incident is being carried out."
Buckingham Palace had no comment to make on the incident, saying it was a matter for the police.
Queen Elizabeth usually spends August and September in Scotland at Balmoral Castle.
It is not the first time intruders have broken into Buckingham Palace.
The most famous security breach was in 1982, when Michael Fagan scaled a palace drainpipe and broke into the queen's bedroom where she was sleeping.
He reportedly sat on the bed and chatted to the monarch before he was arrested.