A man has been arrested after he approached Queen Elizabeth's coffin from a queue of mourners in Westminster Hall.
He was arrested under the Public Order Act and was taken into custody, Metropolitan Police said.
The incident in Parliament occurred at about 22:00 BST on Friday night, the force said in a statement.
The live video feed of the Queen lying in state cut away for a brief period during the incident.
A statement from Scotland Yard said: "Around 22:00 on Friday 16 September officers from the Met's Parliamentary and Diplomatic Protection Command detained a man in Westminster Hall following a disturbance."
A Parliament spokesperson said: "We're aware of an incident in Westminster Hall, in which a member of the public moved out of the queue and towards the catafalque.
"They have now been removed from the hall and the queue restarted with minimal disruption."
Earlier in the evening, the King was joined by siblings Princess Anne, Prince Andrew and Prince Edward, in a vigil in the hall.
The late Queen Elizabeth II will lie in state in Westminster Hall until the day of her funeral on Monday.