Chinese soldiers stationed in Hong Kong have issued a warning to protesters who shone lasers at their barracks, in the first direct interaction with mainland military forces in four months of anti-government demonstrations.
The stand-off with the People's Liberation Army (PLA) came after rallies attended by tens of thousands of protesters earlier on Sunday ended in violent clashes in several locations.
Police fired tear gas and baton-charged the crowds, while some demonstrators threw bricks and petrol bombs at police as night fell.
Protesters concealed their faces in defiance of colonial-era emergency laws invoked by the authorities on Friday, which banned face masks.
Protesters face a maximum of one year in jail for breaking the mask ban.
Police made their first arrests under the new rules, detaining scores of people. Officers tied their wrists with cable and unmasked their faces before placing them on buses.
Some protesters lay in fetal positions on the ground, their wrists tied behind their backs, after being subdued with pepper spray and batons.
"The anti-mask law just fuels our anger and more will people come on to the street," said Lee, a university student wearing a blue mask.
"We are not afraid of the new law, we will continue fighting. We will fight for righteousness. I put on the mask to tell the government that I'm not afraid of tyranny."
Masked protesters dance near Mong Kok Police Station. Source: Getty Images AsiaPac
China's Hong Kong military garrison warned a crowd of a few hundred protesters they could be arrested for targeting its barracks walls in the city with laser lights.
It was the first direct interaction between the PLA and protesters.
Chinese military personnel standing on the roof of the building held up a sign in English and Chinese.
"Warning. You are in breach of the law. You may be prosecuted," it read.
Joining local protesters in the pro-democracy push was Liberal MP Tim Wilson.
The troops in fatigues also shone spotlights on the crowd and used binoculars and cameras to monitor protesters. The protesters eventually dispersed.
In August, Beijing moved thousands of troops across the border into Hong Kong in an operation state news agency Xinhua described at the time as a routine "rotation".
But the PLA has remained in barracks since protests started, leaving Hong Kong's police force to deal with the massive and often violent protests in the Asian financial hub.
The PLA's top brass has warned violence is "absolutely impermissible".
Hong Kong's four months of protests have plunged the Chinese-ruled city into its worst political crisis in decades and pose the biggest popular challenge to Chinese President Xi Jinping since he came to power six years ago.
Riot police clear a street in Prince Edward. Source: Getty Images AsiaPac
