Besieged Hong Kong police officers drew their side arms on protesters, with one of them firing a warning shot into the air as they were pushed back by thick crowds of stick-wielding demonstrators.
The gunshot incident was apparently the first of its kind since the protests began in early June. It came amid a night of violent protests that saw activists hurling gasoline bombs and paving stones and smashing shop windows.
Dramatic video of Sunday night's clashes showed protesters armed with homemade batons forcing a small group of police through an intersection in the city's Tsuen Wan district. After one officer falls to the ground and is surrounded by the crowd, another draws his weapon and fires into the air. Several other officers aim their revolvers at the protesters, halting their advance.
Police, who also fired water cannon and tear gas at protesters, said they arrested 36 people on Sunday, the youngest age 12.
In a Facebook post, the Hong Kong police, quoting Commissioner Lo Wai-chung, said several officers had been injured "after being recklessly attacked by rioters."
"The escalating illegal and violent acts of radical protesters are not only outrageous, they also push Hong Kong to the verge of a very dangerous situation," the government said in a statement.
The protests on Sunday were some of the fiercest since mass demonstrations began 11 weeks ago over a proposed extradition law that would have allowed some people accused of crimes in Hong Kong to be sent to mainland China for trial. Since then, the protesters' list of grievances has expanded to include a demand that Hong Kong's Beijing-appointed leader, Carrie Lam, step down and that an inquiry into alleged police brutality against protesters be opened.
The weeks of demonstrations have disrupted commerce in the Asian financial hub, challenging Lam, whose government has tried a carrot-and-stick approach. They have withdrawn the extradition bill, but also stood aside as Beijing has repeatedly warned protesters that they risk a violent crackdown if the demonstrations continue.
Beijing, too, has weighed in on the protests, warning the pro-democracy forces in Hong Kong that they are "playing with fire" and releasing video of maneuvers by the China People's Armed Police in neighboring Shenzhen – a move apparently aimed at intimidating the demonstrators.
According to The Associated Press, activists have said they plan further demonstrations in the days ahead, including a rally at Hong Kong airline Cathay Pacific's headquarters on Wednesday after the carrier bowed to pressure from Beijing to suspend staff members for their involvement in the protests.