Hong Kong protesters staged a night of New Year's Eve demonstrations in tourist hotspots in Kowloon from Tuesday into early Wednesday, with police deploying a water cannon truck and later firing rounds of tear gas in Mong Kok in efforts to disperse the crowds.

Online calls to fill shopping malls in various districts drew hundreds of protesters earlier in the evening, who strolled and chanted slogans regarding their "five demands" and alleged police brutality against protesters.

"Liberate Hong Kong! Revolution Now," dozens of protesters chanted inside Times Square in Hong Kong's Causeway Bay. "Five demands, not one less!"

In Kowloon's Harbour City, police in riot gear were deployed inside the mall, asking people to produce proof of identity and checking belongings.

A handful of protesters placing flowers at an entrance to the Prince Edward MTR subway station, also in Kowloon, to commemorate protesters they claimed were killed by police during a crackdown on Aug. 31, were subdued by police.

Human chains were also formed by hundreds of protesters across the territory in a show of solidarity.

Anticipating a large turnout for the rallies and a march on New Year's Day, police have warned against violent acts and vowed to take swift action against lawbreakers.

Police seized a stash of gasoline and glass bottles on Tuesday on a hillside in Kowloon, and cautioned that the items could have been used to make firebombs for upcoming public events.

"Jan. 1, see you in Victoria Park!" dozens of protesters chanted during a lunchtime rally in Cheung Sha Wan in Kowloon. Dozens more rallied in the business district of Central on Hong Kong Island.

Wednesday's march was planned to stretch from Victoria Park to Central.

A New Year's Eve fireworks display was canceled to mitigate public safety concerns. It was replaced with a 10-minute light show displayed across Victoria Harbor.

In a New Year's Eve video message titled "Treasure Hong Kong, Our Home," the city's leader Carrie Lam addressed the difficulties facing the people over the unrest, but offered no new solutions.

"I will not shy away from my responsibilities. I will listen humbly to find a way out," she said in the three-minute clip along with three ministers explaining government policies.

While admitting there are shortcomings in the system and deep-rooted problems, Lam said her resolution for 2020 is "to restore order and harmony" in Hong Kong.

Some 40 politicians and religious leaders from 18 countries have in an open letter called on Lam to "instruct the Hong Kong Police Force to exercise restraint" and "respect the right to peaceful protest," according to London-based concern group Hong Kong Watch.

"We appeal to you to use your authority and exercise your responsibility to seek genuine ways forward out of this crisis by addressing the grievances of Hong Kong people...and beginning a process of democratic political reform. It is clear to us that these steps offer some hope of a way forward out of the current crisis," the letter said.

The government dismissed the letter for making "biased and misleading" claims, reiterating that radical protesters have resorted to severe violence while police have exercised restraint in law enforcement.

"We also understand that Hong Kong is being used as a pawn by some in the West to further their own agendas...while ignoring the ongoing serious threats to law and order by radicals that they would hardly tolerate in their own country," the government said in a statement.

More than 6,540 people have been arrested since the movement began in June when the government tried to ram through an unpopular extradition bill that, if passed, would have allowed the transfer of fugitives to mainland China.

Although the government agreed to withdraw the bill in October, the protesters' demands have grown to include an independent inquiry into the use of force by police against protesters, amnesty for all the arrested and greater democracy.

The government has rejected all demands while reiterating that it will stop violence and restore social order first and foremost.

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