Hong Kong police opened fire and hit at least one protester, during a fracas broadcast live on Facebook, as chaos erupted across the city during rush hour on Monday.
Footage showed a police officer drawing his weapon in the eastern district of Sai Wan Ho as he tried to detain a masked man at a road junction that had been blocked by protesters.
Another masked man then approached the officer and was apparently shot in the chest area, quickly falling to the ground, clutching his left side. His condition was not clear.
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Seconds later, two more live rounds were fired by the officer during a scuffle and another masked man went to the ground, although the footage was less clear as to whether he was struck.
Police could later be seen detaining the two men on the ground. The first man had a pool of blood next to him and his body was limp as officers moved him around and apparently tried to tie his hands.
The second man was conscious and talking.
Al Jazeera’s Sarah Clarke, reporting from the area where the incident took place, said more people were beginning to gather as protesters attempt to shut down the city.
“This is a general strike targeting road and the transport system so major thoroughfares, highways have all been blocked,” she said. “There have been huge traffic jams across Hong Kong. Tensions have frayed. The crowds are building. They are gathering because of the escalation in anger after the student was shot this morning.”
The officer involved in the shooting appeared to be from the traffic police, she noted.
A police source, speaking on condition of anonymity, confirmed to the AFP that live rounds were fired at more than one protester in Sai Wan Ho and that a statement would be issued.
Police said earlier radical protesters had set up barricades at multiple locations across the city and warned the demonstrators to “stop their illegal acts immediately”.
Services on some train and metro lines were disrupted early on Monday, with riot police deployed near stations and shopping malls. Many universities cancelled classes on Monday and there were long traffic jams in some areas.
Hong Kong has been convulsed by nearly six months of huge and increasingly violent rallies, with protesters demands including an independent investigation into alleged police brutality.
Activists blocked roads and ransacked shopping malls across Hong Kong’s New Territories and Kowloon peninsula on Sunday during the 24th straight weekend of anti-government unrest.
The latest violence comes after a student died in hospital last week from injuries sustained in a fall as protesters were being dispersed by police.
The protests started when the government tried to push through a controversial and now-shelved extradition bill, but have evolved into a wider call for greater democracy. Many worry that Beijing is meddling in the former British colony’s freedoms, which are guaranteed under the “one country, two systems” formula put in place when the territory was returned to Chinese rule in 1997.