Police fired round after round of tear gas to disperse tens of thousands of demonstrators who defied an official ban and flooded Hong Kong’s residential town of Yuen Long Saturday, bringing their months-long pro-democracy protests to the doorstep of a divided suburb that was the site of bloody mob violence against activists early this week.

The ordinarily quiet cluster of villages near the China border became a flashpoint in the city’s spiraling crisis last Sunday after a mob of suspected gangsters attacked demonstrators, journalists and passersby at a mass transit station in the most barbaric episode of protest-related violence since the unrest began in early June. Police were accused of turning a blind eye as they ran amok, a charge officials denied.

Dressed mainly in black shirts, yellow hard hats and face masks, the de facto uniform of the city’s protest movement, a massive crowd turned out to vent their anger over perceived police inaction during the assault, carried out in two waves of violence over the course of two hours. Organizers of Saturday’s march resorted to satire to evade the official ban; flyers advertised “full gear” activities such as shopping and playing Pokémon GO to justify the large assembly.

“We aren’t calling today a protest,” said Joanne, a 23-year-old professional event organizer who, like many of the protesters, declined to use her given name for fear of legal action. “Some people are here for good food, for sightseeing or for shopping,” she added. “We just all happen to be gathered, and we happen to be angry at the police, but we can’t call it a protest.”

Authorities began trying to clear the roads shortly after 5 p.m., following warnings to leave the area. Residents watched from their rooftops as protesters lobbed what appeared to be smoke bombs in chaotic exchanges with police. Local reports said a round of tear gas was shot in the direction of a home for the elderly, further angering protesters including lawmaker Roy Kwong, a key figure in the movement that has been widely described as “leaderless.” Crowds began leaving en masse just after 7 p.m., shouting “retreat!”

A protester puts graffiti on a police van during demonstration in the district of Yuen Long in Hong Kong on July 27, 2019. Anthony Wallace—AFP/Getty Images

Police in riot gear had been positioned early along the route in anticipation of clashes. The protesters’ anger was palpable, assembling wherever they saw police lines, yelling, calling them names and showing them the middle finger. Some were seen spray-painting graffiti on the side of a besieged police van. A “Yuen Long Manifesto” of unknown origin circulated online, accusing police of colluding with the attackers, labeling them “a band of notorious ruffians” and demanding a public apology.

In the chaos that ensued Sunday, dozens of men wearing white shirts and armed mostly with sticks appeared to target protesters returning from a march in the city center, injuring at least 45 people including a lawmaker and several local reporters. The assailants are believed to be associated with “triads,” organized criminal gangs that have long been accused of acting as paid, extra-legal enforcers of social order. At least 12 men have reportedly been arrested, some with connections to triad groups.

“We are quite angry about what happened on 7/21, it was a riot, they hit and beat any person including children, women and even press,” says Lau, a 50-year-old engineer from Hong Kong’s northern New Territories. He believes the Chinese Communist Party was linked to the attack. “But the underlying problem is the interference from the Chinese government,” he said, “they invited these village gangsters in.”

Read more: Suspected ‘Triad’ Attacks Mark Dangerous New Phase in Hong Kong’s Crisis

Reuters reported Friday that an official from China’s liaison office, local district director Li Jiyi, addressed a banquet in the area more than a week prior and urged locals to chase away protesters if they came “to cause trouble.” One resident told TIME that messages circulated on WhatsApp Sunday evening had riled up villagers to defend the town, and that groups of men soon began gathering at several meeting points before the assault.

Over the past eight weeks, organizers say millions have marched in a series of demonstrations against a now-suspended bill that would have allowed extradition to mainland China. The city’s embattled leader Carrie Lam declared the bill “dead” but refuses to officially withdraw it, and the movement has snowballed into calls for more democratic freedoms as anger toward her Beijing-backed government spilled out into the open and united large swaths of society.

Over the course of the unrest, protesters have broadened their demands to include full withdrawal of the bill, a retraction of the government’s designation of demonstrations as “riots,” amnesty for arrested activists, establishment of an independent inquiry into allegations of police brutality, and universal suffrage as promised under the city’s charter, known as the Basic Law.

Read more: Hong Kong Needs Deep Dialogue of Reconciliation to Move Forward

The former British colony was returned to Chinese sovereignty in 1997 under an agreement called “one country, two systems,” designed to guarantee its autonomy for 50 years. But Beijing’s critics say the city’s freedoms are eroding, and recent years have seen mass demonstrations against attempts to enact legislation that would give China more control over national security, education and electoral processes.

The recent protests have been overwhelmingly peaceful and mostly comprised of young activists mobilized online, though sporadic clashes have occurred between police in riot gear and small groups of more radical demonstrators. Police have on several instances deployed tear gas, pepper spray and other crowd control measures to disperse them, sometimes resulting in injuries and eroding public trust in law enforcement.

The government has done little to heal the divide. In a press conference Monday, Lam failed to appease her critics when she conflated the mob violence with vandalism of Chinese government property committed by a small group of protesters, condemning aggression by both sides. She has so far refused to offer concessions acceptable to the protesters or in any way promote dialogue, and with three years left to serve has shown no sign of stepping down.

— With reporting by Laignee Barron and Abhishyant Kidangoor / Yuen Long

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