In March 2011 , the square was occupied by a crowd protesting against the UK Budget and proposed budget cuts . During the night the situation turned violent as the escalation by riot police and protesters damaged portions of the square . In November 2015 a vigil against the terrorist attacks in Paris was held . Crowds sang the French national anthem , '' La Marseillaise '' , and held banners in support of the city and country
terrorist attacks in Paris
November 2015 Paris attacks
Trafalgar Square