A Hong Kong police officer shot a protester on Monday amid anti-government demonstrations.

Video footage showed a scuffle between black-clad protesters and a police officer, who moments later shot one of the protesters at close range. The protester was then seen lying in a pool of blood with his eyes wide open. He was taken to the hospital, where he underwent surgery and is in stable condition.

Hong Kong police confirmed the incident in a tweet, saying that police officers in two other districts had "drawn their service arms from their holsters."

Meanwhile, a man supportive of the government was set on fire following a heated debate with protesters. A man clad in black with a face cover poured gas on the man and lit a torch on him. He was reportedly taken to a hospital. His condition is unclear.

Read more: 'Too late' for Hong Kong government to gain citizens' trust

'Widespread violence'

Hong Kong leader Carrie Lam described the latter incident as an "inhumane act."

"Citizens are very worried whether they can live in the city safety," she said during a press conference. "The widespread violence must be strongly condemned by the whole of society."

Read more: West reluctant to criticize China over Hong Kong stance

'Police brutality'

In an interview with DW, pro-democracy activist Joshua Wong called on authorities to launch an investigation into police brutality.

"We are calling on the Hong Kong government to set up an investigation into police brutality. Now is the time to give us back free elections," Wong said. "If the Hong Kong government would listen to the voice of Hong Kong people, it would just let the world announce the death of 'one country, two systems.'"

Read more: 'Hong Kong mob' — How mainland Chinese see the democracy movement

Tense atmosphere

DW's Mathias Bölinger in Hong Kong said tension was evident across the city. Office workers coming out onto the streets to demonstrate during their lunch breaks were "fired upon with tear gas," he said.

Read more: Hong Kong: Will violence kill the pro-democracy movement?

Joshua Wong said on Twitter that a fierce crackdown had begun early in the day and showed footage of clashes between police and protesters.

"Barely 9 o'clock in the morning, and across the other side of town, in Kwai Fong, a traffic cop gone berserk on a motorcycle is running protesters over," Wong wrote.

Escalating violence

The violence comes just a week after a student died in hospital after falling from a building, when protesters were being dispersed by police.

Hong Kong has been rocked by protests since June, when residents took to the street to reject an extradition treaty with China.

Since then, the movement has snowballed into larger pro-democracy demonstrations that have been repressed by security forces. Protesters have taken a strong stance against police brutality and China's influence over the territory.

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ls/rt (Reuters, AFP)