Earlier in the day, riot police stormed into New Town Plaza mall – and Telford Plaza in Kowloon Bay – to chase after and subdue protesters, triggering clashes between officers and those in black.

Families and onlookers were caught up in the maelstrom with one young boy appearing to be hit by pepper spray intended to drive protesters away. A first-aider tended to the child in Kowloon Bay who was heard saying his eye hurt. A woman in Sha Tin who argued with protesters was spray-painted in the face and was helped away by paramedics.

While the so-called Christmas shopping protests took place in at least seven malls across the city in the afternoon, elsewhere thousands gathered in Tamar Park in Admiralty to voice support for the city’s beleaguered police force and condemn violence by radical activists.

Protests see travellers avoiding Hong Kong in record numbers

In New Town Plaza, demonstrators took over the atrium from 2pm while others marched around the mall, singing protest songs and shouting anti-government and anti-police slogans.

They vandalised a restaurant under the Maxim’s chain – a popular target of protesters’ ire on account of critical remarks made by the founder’s daughter Annie Wu Suk-ching – shouted at diners and sprayed graffiti on the storefront.

In another incident, a small crowd surrounded a woman, pushed her around and threatened her for about 15 minutes. They accused her of taking pictures of protesters’ faces, then grabbed her phone and smashed it.

The woman, who gave her surname as Ng, said she had not taken any photos of people’s faces.

“What power do you have to search my identity card or phone?” she said afterwards.

“We are all Hongkongers, a family. Why do we need to give in to political conflict and deprive others’ freedom? I feel some people have lost all reason.”

A 16-year-old secondary school pupil, who only gave her name as Olivia, said she hoped Sunday’s protests would force businesses to cut ties with the government or police.

“Since the movement reached this stage, neutrality is essentially equal to supporting the government or police,” she said, adding the force must be held accountable for its handling of demonstrations.

Clashes soon broke out as police entered to stop protesters blocking mall entrances and staircases.

Officers used batons and pepper spray on protesters, who threw projectiles and water in return. A few arrests were made. Officers also pointed crowd-control guns at those gathered inside the mall.

As police retreated, a smoke bomb was thrown into the bus terminus outside Sha Tin railway station. The force condemned the “extremely irresponsible” act that “could have caused chaos and panic”.

Similar scenes played out at Telford Plaza and Metroplaza in Kwai Fong, where protesters hurled verbal abuse or chanted slogans at diners, while disrupting the operation of restaurants.

There were also protests in Times Square in Causeway Bay, PopCorn in Tseung Kwan O, Cityplaza in Tai Koo Shing and Harbour City in Tsim Sha Tsui.

Over in Tamar Park, those rallying to offer their backing to police waved national flags.

“What’s the problem with police doing their job, which is to protect Hong Kong?” tourism industry worker Joe Yeung, 51, said. “If there was no violence from the rioters, there would be no tear gas.”

Leo Leung Hoi-fung, organiser of the pro-police rally, called on people to support “blue” shops – the colour symbolising the pro-establishment side – such as Maxim’s. Police estimated 11,200 attended the event at its peak.

Meanwhile, at a separate rally at Edinburgh Place in Central, hundreds of social workers vowed to stage a three-day strike from Tuesday.

One social worker in his mid-20s, who gave his surname as Yeung, said the strike was a change in tactics after months of increasingly violent protests, which had resulted in more than 6,000 arrests.

“Organising a strike is more powerful than violent action,” Yeung said.

According to Patrick Lam, a member of the All-In Strike Committee of the social welfare sector, at least 2,000 social workers so far had said they would take part.

“We are not sure how many units or services will be closed, but we are expecting a vast effect,” he said.

Financial Secretary Paul Chan Mo-po, writing on his blog on Sunday, again expressed concerns that the months of unrest would drive away foreign investors and warned that Hong Kong would lose its competitiveness in holding international conferences, exhibitions and major events.

Chan also spoke to the man’s wife during the visit, which was revealed in a Facebook post by pro-Beijing legislator Elizabeth Quat on Sunday.

“[Chan] had asked me about the man’s condition several times before,” Quat wrote. “[He] brought a handwritten card and the man was very pleased when he saw the financial secretary.”

Later on Sunday night, scores of people gathered outside the upmarket Pacific Place mall in Admiralty to remember Marco Leung Ling-kit, who fell to his death hanging a banner from an external wall. Some laid flowers on the pavement, while others lit candles and sang songs. People also chanted popular protest slogans such as “Liberate Hong Kong; revolution of our times!”

In Mong Kok, near the Langham Place shopping centre, a confrontation broke out at about 9pm between dozens of residents and police, who used pepper spray to disperse the crowd. They also raised a blue flag warning that those there were taking part in an illegal assembly. Police had stopped and searched a man on the street, sparking verbal abuse from people around.

A heavy police presence remained on Portland Street outside Langham Place two hours after the initial incident. At another flashpoint in Mong Kok, outside the Hang Seng Bank offices on Nathan Road, officers fired pepper balls to disperse a crowd. A reporter was hit and attended to by volunteer medics.

Several rounds of tear gas were fired on Sai Yeung Choi Street South after police raised a black warning flag.

At about 11.45pm, police fired tear gas again, on Nathan Road near Soy Street, as they headed towards their vehicles. But there was no sign of protesters or any clashes.

Reporting by Ng Kang-chung, Jeffie Lam, Karen Zhang, Alvin Lum, Albert Han and Danny Mok