Extinction Rebellion: Is this a genuine Banksy?
Speculation is mounting that Banksy was at Extinction Rebellion's London protests after the appearance of a mural at the group's Marble Arch base.
The stencilled street art of a girl along with the words "From this moment despair ends and tactics begin" was found on a wall overnight.
The site had been occupied by climate activists for nearly two weeks until protests ended on Thursday. Banksy has not confirmed if he was behind the work.