Hong Kong's embattled leader Carrie Lam has invoked colonial-era emergency powers for the first time in more than 50 years in a dramatic move intended to quell escalating violence in the Chinese-ruled city.
Ms Lam, speaking at a news conference, said a ban on face masks would take effect Saturday under the emergency laws that allow authorities to "make any regulations whatsoever" in the public interest.
"We believe that the new law will create a deterrent effect against masked violent protesters and rioters, and will assist the police in its law enforcement," she said.
But even before the new rule was confirmed, protests against it began across the Asian financial hub, with hundreds of office workers wearing masks gathering to march.
A student wears a helmet with writings reading 'Liberate Hong Kong, revolution of our time'. Source: AAP
It was not clear how the government would implement a ban in a city where many people wear masks on a daily basis to protect themselves from colds and flu, especially after an outbreak of the deadly Severe Acute Respiratory Syndrome (SARS) in 2003.
"After so many months the government has refused to answer our demands," said one protester, who asked to be identified as just Chan, at a demonstration in the city's Central district.
"Police brutality is becoming more serious and the set up of an anti-mask law is to threaten us from protesting," said the 27-year-old financial industry worker.
Pro-democracy supporters and local residents stand off with police at the Tai Koo MTR station. Source: Getty Images AsiaPac
Anti-government protests have gripped the former British colony for months, plunging it into its biggest political crisis in decades and posing the gravest popular challenge to Chinese President Xi Jinping since he came to power.
The protesters are angry about what they see as creeping interference by Beijing in their city's affairs despite a promise of autonomy in the "one country, two systems" formula under which Hong Kong returned to China in 1997.
China dismisses accusations it is meddling and has accused foreign governments, including the United States and Britain, of stirring up anti-China sentiment.
What began as opposition to a proposed extradition law, that could have seen people sent for trial in mainland courts, has grown into a call for five demands, including universal suffrage and an inquiry into alleged police brutality.
Protesters, some wearing gas masks and helmets, marched past some of the city's most expensive real estate including British bank HSBC's head office, on Friday, calling out for "five demands, not one less".
"We need to stay strong for Hong Kong and that is why I am joining this flash mob protest," Chan said.
The protests have been inflamed by the police shooting of a teenaged secondary school student on Tuesday during a clash, and more rallies are expected later in the evening and over the weekend.
Police said the officer involved in the shooting acted in self-defence because his life was under threat. The teenager, the first protester hit by live fire during months of unrest, is in hospital in a stable condition.
Riot police moved in to districts across Hong Kong overnight, firing tear gas at a chanting crowd in a residential area, while rail operator MTR Corp shut several stations as violence escalated.
All stations were operating normally on Friday morning.
MTR's operations director Adi Lau urged protesters to stop damaging station facilities and rail tracks, saying it could hinder services and pose a severe danger to passenger safety.
Pro-Beijing groups have also been pushing for legislation to ban face masks at demonstrations but the government has declined to comment on whether it was considering one, or broader emergency laws, stating it would study existing legislation to cope with the protests.
Authorities have already loosened guidelines on the use of force by police, according to documents seen by Reuters.
