Supporters of the online protest group Anonymous have taken part in a series of demonstrations to coincide with Bonfire Night.
The group has taken for its logo the image of Guy Fawkes made famous by the film V for Vendetta. In the film and the graphic novel it's based on, V overthrows a corrupt government by blowing up the Houses of Parliament.
Demonstrators in Madrid tried to march on the country's parliament but were stopped by police. In London, protesters clashed with police in Parliament Square. In Washington, demonstrators peacefully protested outside the US Justice Department.
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