Police cracked down on Hong Kong’s Polytechnic University Monday after a days-long siege on the protester-occupied campus spawned some of the most violent confrontations since the anti-government demonstrations began six months ago.

Following protracted fighting, several protesters attempted to flee the campus and avoid arrest Monday morning, but were driven back by a barrage of tear gas.

Dozens of people were arrested as clashes broke out nearby the university, including several who were seen detained outside a high-end hotel in the city’s tourist district of Tsim Sha Tsui (often referred to by it’s abbreviation TST).

An unknown number of students remain hunkered behind the walls of Polytechnic University, which police are not allowing press to access.

As fears of a bloody showdown mount, Hong Kong’s courts granted protesters a major victory Monday, striking down a controversial face mask ban that the government had enacted in October. The High Court found the ban on face coverings at all public gatherings a violation of the territory’s mini-constitution, known as the Basic Law.

Imposed under colonial-era emergency regulations that the government had invoked in hopes of quelling the months-long unrest, the ban instead inflamed public anger and prompted more clashes.

The court’s decision was greeted with cheers on the streets.

“It shows that what the government is doing may not be legal and right, they just want us to feel afraid,” said Billy, 35, a white collar worker who came out to Hong Hom to show his support for protesters trapped inside Polytechnic.

Meanwhile, the government has warned that the unrest has “reduced the chance” that upcoming local elections will be held. The polls, slated for Nov. 24, are seen as a referendum on Hong Kong’s protest movement and their deferral is likely to exacerbate tensions further.

From Monday afternoon, many family members and friends convened on a footbridge that leads into the campus. Unable to get inside, they hope their presence will send a message to the phalanx of officers gathered nearby. “Release the people,” some shouted.

“My sister is inside,” said Joy, a 29-year-old officer worker who joined the other relatives on the footbridge. “I don’t know what to do. I know I can’t help her get out but I want to be closer to her. My mother is quite worried but I told her to stay home.”

Other well-wishers gathered in a park about half a kilometer from the university, sitting under a large Christmas illumination that read “Peace.”

“It’s been more than five months, everyone is very tired,” said Tsoi, a 28-year-old masters student at the university. “This feels like the last chance to gather all the people and have a stand.” He added that he had friends inside the campus. “They are very tired and very worried. But most of them say they will stay and fight until the end.”

As night fell, the crowd swelled with office workers turning out to join the protest. “I’m afraid, but if we don’t stand up for them the students won’t have any chance to get out of there,” said Cuson, a 40-year-old public sector worker.

Labour Party legislator Fernando Cheung was also among the throng.

“It’s a humanitarian catastrophe,” he told TIME. “We have hundreds of young people trapped by police, not allowing them to leave, and we know the food and water and other materials are limited.”

He estimated that around a hundred protesters were under 18 and 40 were under 16.

A protester stands in front of a broken pane of glass during a demonstration in Jordan district of Hong Kong, China, on Monday, Nov. 18, 2019. Kyle Lam/Bloomberg via Getty Images

Escalating unrest

In Central, the city’s main business district, protesters returned to the streets at lunchtime chanting “Save Poly U.” On social media channels used by protesters, calls circulated for supporters to come and help however they can. Many responded by barricading roads in neighborhoods near the university, attempting to disrupt traffic and divert the police’s attention. The gatherings were met with tear gas.

“The police blocked all the exits, we are unable to go in to help them [the students] come out so we’re trying to come out in different locations, TST, Mong Kok, to weaken the power of the police force,” said Grace, a 22-year-old accountant who skipped work to demonstrate.

Protesters have been barricaded inside the fortress-like campus, stockpiling Molotov cocktails and other weapons, since last week after an escalation in the unrest prompted students to hole up in several universities.

A standoff culminated Sunday as police attempts to enter the campus were met with fierce resistance.

Officers surrounded the university and warned that anyone choosing to remain in the area could be charged with rioting. If met with further attacks, the police threatened they could use live ammunition. At least three people have been shot with live rounds since the demonstrations began. A man was also set on fire after getting into an argument with protesters.

Throughout Sunday night and Monday, protesters countered volleys of tear gas and rubber bullets with gasoline bombs, slingshots and bows and arrows. Police advances, including an attempt to get through with an armored vehicle, were repeatedly repelled. Smoke billowed above the campus as barricades were set ablaze. One police officer was stuck in the leg with an arrow, while students said some protesters suffered hypothermia after they were doused by water canons in the night.

As dawn broke, riot police breached the main entrance, reportedly making some arrests. But explosions seen on live feeds appeared to push the officers back again, at least temporarily.

The Polytechnic University campus, on the end of the Kowloon peninsula, adjoins the the Cross Harbour Tunnel—a vital artery that connects the city’s most populous urban area with the banking and commercial districts of Hong Kong Island. Protesters have forced the tunnel’s closure for days by erecting burning barricades across the tunnel approach roads, razing toll booths and hurling objects from a footbridge that leads from the campus across the toll plaza.

The pitched battles at the university and the looming threat of live rounds mark a sharp escalation in Hong Kong’s protests, which started out with peaceful marches in June. The movement has increasingly turned more violent as police attempts to quell the unrest drive more protesters into adopting radical tactics.

Galvanized by the death of a student who fell during demonstrations earlier this month, protesters have shifted from weekend rallies to holding daily strikes that have snarled traffic and prompted schools to cancel classes for over a week.

University students, who are at the front lines of the movement, occupied five university campuses last week, fortifying the entrances, blocking nearby roads and smashing up adjacent subway stations. But while the other campuses emptied over the weekend, the hardline holdouts filtered into Polytechnic University, preparing for a fight.

Police have appealed to those inside to “drop their weapons,” remove their masks and leave in orderly manner. But it seems unlikely protesters will follow the order, given they would likely be arrested.

In a post circulating on the Telegram social media channels used by protesters, some claiming to be inside the campus have vowed not to surrender.

“Us students will remain until the very last moment,” one user said, before adding, “We would rather die if we don’t have freedom.”

—With reporting by Laignee Barron, Amy Gunia, Abhishyant Kidangoor and Hillary Leung / Hong Kong

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