British police said on Sunday a man had been arrested after a car crashed into the gates of Buckingham Palace in central London.
Grainy images on social media showed a car at the front gates of the palace. British media quoted a witness as saying they had heard "a loud bang".
Police said the incident had occurred in the early hours of Saturday morning.
"Armed officers arrested a man at the scene on suspicion of criminal damage," London police said in a statement. "He was taken to hospital where following assessment he was sectioned under the Mental Health Act. The matter is not being treated as terror-related."
Buckingham Palace said no member of the royal family was resident at the time of the incident and repairs to the gates were underway.
