Continuing a yearly tradition which started in 2011 alongside the Occupy movement, activists in cartoonish Guy Fawkes masks marched through the streets in cities across the world on Thursday, protesting injustice, censorship, and corporate greed, all in the name of Anonymous.

In Central London, thousands of people, called “anti-capitalist rioters” by Scotland Yard, rushed the gates of Buckingham Palace, which was guarded Thursday evening by men with billysticks, checkered caps, and bright-yellow vests. As is customary, many of the demonstrators gathered at the nearby Trafalgar Square, only a stone’s throw from the Charing Cross Police Station, which has held in the past more than one of Anonymous’s more infamous members.

Just north of the tube at Trafalgar, police projected in a large font across the face of the National Gallery: “Officers may require you to remove face coverings.” The officers, targeted with fireworks by some of the pranksters, began to cordon off the square shortly after 9pm local time.

Near the high-end offices and restaurants to the west at St. James Square, a police car was set on fire and left to burn with its windshield smashed in.

#MillionMaskMarch and the @NationalGallery is clearly taking sides with a banner communication from the police pic.twitter.com/CJL2oSf6rL — soso (@sonyfromtheblog) November 5, 2015

Police block #MMM2015 route to regent street pic.twitter.com/r25pNkwLRM — Damien Gayle (@damiengayle) November 5, 2015

In the U.S. capital, a few hundred anti-establishment demonstrators gathered more quietly at the Washington Monument before marching to the White House.

A Washington Post reporter who attended the event reported—naively—that the protesters “did not seem aware that Time Warner made a profit on each of the masks sold,” citing an August 2011 article by New York Times columnist Nick Bilton.

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Indeed, Time Warner does profit from the sale of its officially licensed V for Vendetta merchandise, but the widely popular mask of Guy Fawkes—also known as Guido Fawkes of the infamous 1605 Gunpowder Plot—can be purchased alternatively through tens of thousands of online sellers, none of whom pay Hollywood a dime. Aside from the fact that the mask pre-dates by more than a hundred years the film by the Wachowskis, and the Alan Moore comic on which it is based, U.S. intellectual property laws do not grant Time Warner exclusive rights to reproduce the visage of a well-known historical figure.

One arrest at the #MillionMaskMarch outside the White House just happened now #anon #ows pic.twitter.com/VG0MxAqOc2 — Occupy Wall Street (@OccupyWallSt) November 5, 2013

According to the Post, the National Park Police confirmed at least one arrest in Washington, D.C., near the White House “on a charge of assault on a police officer.” The protesters, who championed a plethora of causes from climate change and police brutality to mass surveillance, marched through the streets of the capital, occasionally halting traffic and vandalizing public property with political slogans. Photos on social media showed the demonstrators gathered outside the U.S. Environmental Protection Agency, where a revolving door’s glass had been shattered.