A protester was shot and seriously injured by police in central Hong Kong on Monday during a mass demonstration while activists set another man on fire in the northeastern area of the territory, according to local media and the police.

Footage uploaded to media sites showed a police officer shooting a mask-wearing protester -- while grappling with another masked man -- at point-blank range, at an intersection in Sai Wan Ho on the eastern part of Hong Kong Island.

The 21-year-old man underwent emergency surgery on his liver and kidneys and remained in a critical condition afterwards, the South China Morning Post reported, citing a medical source.

A total of three live rounds were fired around 7:20 a.m., according to the newspaper. Tear gas was also fired in the residential area as pepper spray failed to disperse the crowd.

(A police officer points his gun to a masked protester.)
[Screenshot from Hong Kong's Standnews website]

Police spokesman Kwok Pak-chung told a press conference that the officer discharged his weapon at the protester out of fear that the man was attempting to steal his revolver.

As another protester approached, he fired two more shots, but struck no one, according to the spokesman.

The shooting comes a week after Chinese President Xi Jinping told embattled Hong Kong leader Carrie Lam, in Shanghai, that restoring order is the priority for the Chinese territory.

"If there is still any wishful thinking that by escalating violence, the Hong Kong SAR government will yield to pressure to satisfy the so-called political demands, I am making this statement clear and loud here -- that will not happen," Lam told reporters at a briefing late Monday.

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"Violence is not going to give us any solution to the problems that Hong Kong is facing. Our joint priority now as a city is to end the violence and to return Hong Kong to normal as soon as possible," she said.

The protester is believed to be the third person injured by a live round fired by police during the months-long anti-government protests. The two others were shot and wounded in early October.

A 27-year-old witness who heard all three shots said he saw a man dressed in black bleeding from the stomach but who appeared conscious when loaded into an ambulance.

The man said he did not understand why police shot an apparently unarmed protester.

In Ma On Shan in the New Territories, a man who was apparently arguing with protesters was seen doused with a flammable liquid and set on fire in the afternoon, according to a video circulating on social media.

He was hospitalized with burns and remains in critical condition, the hospital authorities said. The police said "rioters" were responsible for setting the man on fire and they are investigating.

Elsewhere, protesters tried to disrupt traffic by erecting roadblocks as part of a citywide general strike, while police fired tear gas to disperse them.

A fire was set in a subway carriage, causing commuters to flee in chaos, according to local reports. Services were suspended on both the metro and railway due to some stations being vandalized and debris being tossed on rail tracks.

In the business district Central, police fired tear gas at protesters blocking a road junction at lunchtime, causing dozens of office-goers to seek refuge inside business buildings.

At both Chinese University of Hong Kong and Hong Kong Polytechnic University, police chased protesters inside the campuses and fired tear gas to disperse them.

By nightfall, protesters assembling in the populated Mong Kok district in the Kowloon Peninsula and the shopping district of Causeway Bay in Hong Kong Island were dispersed by police with tear gas.

At least 64 people were injured on the day, including the two critically injured men, the health authorities said.

The police said 266 people were arrested in the past week for crimes including unlawful assembly, possession of weapons, criminal damage, assaulting a police officer, and violating the anti-mask law.

Hong Kong has seen increasingly violent clashes between police and demonstrators in recent months. Last week a university student injured in a fall at a parking garage during a police operation succumbed to his injuries, marking the first protest-related fatality.

The mass protests were sparked by a now-withdrawn bill that sought to facilitate extraditions to mainland China.

However, the protesters' demands have now widened to include police accountability and democratic reform in the former British colony.