Protest organiser the Civil Human Rights Front claimed the turnout had surpassed the 1.03 million estimate for the first major rally against the extradition bill in June. Police put the figure at 47,000 during the march while another 13,000 were still at the starting point.

It was a show of solidarity to push for the protesters’ core demands, including an independent investigation into police conduct over nearly seven months of social unrest, amnesty for all those arrested, and universal suffrage.

“I think the protests will continue as the chief executive is not responding in any sense, and from her so-called video to celebrate the new year we don’t see her showing any regret for what she did,” a 16-year-old student at Victoria Park said.

An art gallery employee at the protest said: “As time goes by, people might start to feel numb, therefore we should remain sensitive.”

The trouble started about two hours into the march at 4.30pm, when radicals vandalised an HSBC branch on Hennessy Road in Wan Chai. The protest movement has turned against the banking giant, which it accuses of having a hand in a recent police crackdown on Spark Alliance, a major fundraising platform for protesters.

A police squad, including masked undercover officers, arrived at the scene and arrested five people, one of whom was dragged face-down on the ground, angering other protesters. Officers used pepper spray and fired pepper balls at them, and resorted to tear gas to disperse a crowd that began hurling umbrellas and other projectiles at them. Petrol bombs were also thrown at them.

Just after 5.30pm, the organisers announced they had been ordered by police to end the march because of the violence. Thousands of protesters were still waiting to set off from Victoria Park at the time.

“On the first day of 2020, police dismissed the first licensed assembly of the year with an absurd excuse. The Hong Kong government has shown its unwillingness to listen to the voices of the masses, infringing the right of assembly of Hong Kong citizens,” the front complained in a statement.

With the march suddenly over, many became defiant and refused to leave the streets, spilling out into Causeway Bay, Wan Chai and Central.

The violence escalated as night fell. At least five HSBC outlets were smashed up or firebombed, prompting the banking giant to issue a statement saying: “We strongly condemn the acts of vandalism and damage directed at our premises repeatedly in the last few days. We believe these are unjustified.”

Bricks were dug up and fires set to block roads, causing traffic chaos, while graffiti was painted on the outer wall of the High Court, insulting judge Anthea Pang Po-kam, who sent three localists to prison over the 2016 Mong Kok riot.

Hong Kong rings in new year with muted celebrations, defiant protests

The Department of Justice condemned the vandalism, warning that personal attacks against judges “would severely undermine the authority of the courts and damage public confidence in the judicial system”. Law Society president Melissa Kaye Pang expressed shock over the attack.

By 7pm, police had fired multiple rounds of tear gas in Central, Wan Chai and Causeway Bay, and deployed water cannons to chase protesters off the streets.

Causeway Bay became a flashpoint, and police made mass arrests outside the Sogo department store, where around 70 people were made to squat on the ground as they were searched and processed.

Some complained they had not done anything wrong, but were trapped after police cordoned off a sizeable area they happened to be within.

Officers also raised a flag at journalists at the scene, warning them they were taking part in an illegal assembly.

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Democratic Party lawmaker Ted Hui Chi-fung said he was pepper-sprayed by police in Causeway Bay earlier as he monitored their actions.

“Officers asked journalists and me to get back on the pavement, which we all complied with. Basically, I was cornered at a shopping mall,” Hui said. “Then they removed my mask and sprayed at me without warning.”

Police said at least 400 people were arrested on Wednesday mostly for illegal assembly and possession of offensive weapons, making it one of the biggest mass arrests in a single day.

Sources said police had changed their strategy from usually dispersing crowds to making mass arrests.

The police operation continued late into the night as officers took control of one occupied area after another. They also set up roadblocks along major routes and were seen checking buses.

The New Year’s Day march was led by newly elected district councillors from the opposition camp, who also raised funds for Spark Alliance, filling at least six donation boxes with HK$100 and HK$500 (US$13 and US$64) notes.

Newly established trade unions also set up booths along the route, urging demonstrators to join up and help the movement with possible strike action.