British police say a man has been arrested after scaling a gate outside Buckingham Palace.

The Metropolitan Police force says the 21-year-old was arrested for trespassing as he dropped to the ground Friday afternoon.

He was not carrying a weapon and will undergo a mental health assessment.

Queen Elizabeth II was not at the palace.

A royal spokeswoman declined to comment, saying security was a matter for the police.

Several intruders have breached security at the queen's London residence over the years, including a man convicted of murder who climbed a wall in May while the queen was at home.

In 1982, Michael Fagan managed to sneak into the queen's private chambers while she was in bed. Elizabeth spent 10 minutes chatting with him before seeking help.