An Anonymous protest in London led to numerous arrests Saturday in the United Kingdom. Anonymous, known as a radical group centered around hacking and other electronic activist actions, is recognizable by their use of the Guy Fawkes mask in their protests and media projects.

According to Reuters, the Anonymous protest took place in central London, beginning at the famed Trafalgar Square and moving in an organized march to the location of the British Parliament. The march involved several hundred activists, and was part of a coordinated, but decentralized, global action promoted by the Anonymous “hacktivist” group.

An Activist During The Anonymous Protest Near Big Ben [Image by Ben Pruchnie/Getty Images]

The Anonymous protest was scheduled in London and around the world for November 5, a date with particular relevance in British history. On November 5, 1605, a former British soldier and Catholic activist named Guy Fawkes was arrested while attempting to carry out a scheme to blow up the British Parliament building which housed the House of Lords with some 36 barrels of gunpowder, an event now immortalized in Britain as The Gunpowder Plot. According to USA Today, authorities were tipped off by an anonymous letter, and Fawkes, having been left in the cellar to set the fuse on the explosive powder kegs the next morning, was found and arrested. British Parliament later made the event a holiday, which has been often celebrated in Britain by burning Fawkes in effigy.

Later, British author Alan Moore wrote the graphic novel V For Vendetta, featuring a revolutionary character who resists an authoritarian British government and conceals his face with a mask with the features of Guy Fawkes. The graphic novel was later turned into a popular film by the same name, directer by James McTeigue. The modern group Anonymous, inspired by the original story and its use in fiction, took on the Guy Fawkes mask as a symbol of both revolution and the solidarity inherent in anonymity.

The Anonymous protest in London was a part of an annual international event called the Million Mask March, referring to the group’s signature masks. The event is centered around the ideals of anti-capitalism and the defense of civil liberties. The Guardian reports that the Anonymous protest went off without much incident or violence, but some 47 people were arrested. The majority of those taken into custody were arrested for minor drug offenses and obstruction of police business, officials claim.

Scotland Yard, the principal British policing agency, set stringent limits on the Million Mask March Anonymous protest this year, fearful of a repeat of the violence they claim occurred last year in 2015. In that event, several police officers and a police horse were apparently injured by Anonymous protesters. This year, Scotland Yard and local authorities set limits on the time during which the protest could take place and bulked up their official presence. Dozens of police in riot gear and with numerous riot-ready vans were to be seen in Trafalgar Square and along the Anonymous protest route.

An Activist Holds A Sign At The London Anonymous Protest {Image by Jack Taylor/Getty Images]

The Anonymous protest in London drew people from around the United Kingdom, and indeed, the world. Most protesters who were interviewed by the local and international press seemed committed to peaceful means of protest. One anarchist activist, Aztecarna Peatonito, who had traveled from Mexico to attend last year’s event, expressed a common sentiment in the crowd.

“We tried for six years to get the press to take us seriously. It is only when we wore the masks that we started getting attention. Anyone who is violent is not with us,” Peatonito said.

According to U.K. media outlet the Independent, many of the obstruction charges resulted from members of the Anonymous collective joining the protest refusing to remove their Guy Fawkes masks, which was declared an offense in advance of the protest. Other arrests were for minor property damage and the possession of cannabis.

[Featured Image by Jack Taylor/Getty Images]