During the song One Day More, where an actor waves the famous red flag, members of the group stormed the stage with banners emblazoned with Just Stop Oil.

A video shows the actors on stage continuing to perform the number before they step back while the area is cleared and the safety curtain comes down.

The crowd boo while one member of the group addresses the auditorium.

They then locked themselves to the set, prompting the Sondheim Theatre to be evacuated.

Just Stop Oil member Hannah Taylor said: "The show starts with Jean Valjean stealing a loaf of bread to feed his sister's starving child. How long before we are all forced to steal loaves of bread? How long before there are riots on the streets?

"The show cannot go on. We are facing catastrophe. New oil and gas means crop failure, starvation and death. It is an act of war on the global south and an utter betrayal of young people."

Poppy Bliss, who also took action, added she is "absolutely terrified for my future."

"I don't want to be disrupting people's evenings out, but I have been left with no other choice. Our government is betraying the young and putting everyone's futures on the line for the sake of a few votes.

"I am doing this because I am desperate."

Subsequent videos show members of the group explaining why they took the action, wearing t-shirts saying: "The show can't go on".

The Metropolitan Police said: "At approximately 21:00hrs on Wednesday 4 October police were called to reports of a small number of protesters at a theatre in Shaftesbury Avenue.

"Officers are on scene and dealing."

Sky News has contacted Delfont Mackintosh Theatres for more information.

It's the latest in a string of public protests for Just Stop Oil, who have in the past few months disrupted high-profile sporting events, such as The Ashes and Wimbledon, as well as carrying out walking protests through the capital during rush hour.

The group were also accused of causing criminal damage by a government minister, after they sprayed the Department for Energy and Net Zero with orange paint.

Last month, Fossil Free London carried out a similar protest at Sadler's Wells theatre during a performance of a ballet version of Romeo & Juliet, demanding an end to the involvement of Barclays in the production.

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