Graffiti was sprayed on the statue former prime minister Sir Winston Churchill in Westminster to add the words “was a racist”.
The writing was added to the base of the memorial in Parliament Square during the Black Lives Matter protest on Sunday.
Video footage showed a small crowd of demonstrators chanting “Churchill was a racist” and “Boris [Johnson] is a racist”. A smaller group of people stood around the statue in an apparent attempt to protect it.
Four uniformed police stood nearby as the crowd took photographs.