Early on Thursday evening, the mood in Lan Kwai Fong, a rowdy night life district known for its booze-soaked Halloween parties, was noticeably muted. While the streets were still filled with revelers in costumes, compared to years past there were fewer Halloween decorations and more security and journalists.

At around 7 p.m., dozens of protesters wearing masks of government leaders like Xi Jinping and Carrie Lam gathered in the district. Amid blaring music from nearby bars, the protesters began shouting slogans like “Fight for freedom, stand with Hong Kong.”

Not long after, a tense standoff formed between the police and protesters. Officers soon declared the gathering an unlawful assembly and took the nearly unprecedented step of ordering an immediate evacuation of the district.

Later in the evening, with the area blocked off, a reveler dressed as Snow White could be seen coughing in the tear gas as tourists took selfies.

The night included multiple clashes between protesters and police elsewhere around the city. The police fired canisters of tear gas at protesters outside the Mong Kok police station in the Prince Edward district, and later in the heart of the central business district, which includes Lan Kwai Fong.

The protest movement began as a fight over a now-withdrawn extradition bill and has expanded its demands to include free elections and an independent investigation into the police’s use of force. But after agreeing to withdraw the extradition bill, the government has since then refused to budge on the other demands, summed up by protesters under the slogan “five demands, not one less.”