Sir Ian McKellen in hospital after falling from stage

The audience were informed that the remainder of the evening performance had been cancelled and they were evacuated from the premises.

A BBC journalist, who saw the play, said the veteran stage and screen actor was in a scene involving the Prince of Wales and Henry Percy when he fell off the front of the stage.

The actor was heard to cry out in pain as staff rushed to help.

Player Kings, a production of Henry IV, parts one and two, adapted and directed by Robert Icke, is due to move to the Bristol Hippodrome in July and will also be staged in Birmingham, Norwich and Newcastle.

Sir Ian's representatives and the ambulance service have been approached for comment.