The Hong Kong government on Friday invoked an emergency law to ban the wearing of face masks at public demonstrations, with a stated aim of deterring violence amid intensifying anti-government protests.

In issuing the ban, which became effective Saturday, Hong Kong invoked its Emergency Regulations Ordinance for the first time since returning to Chinese rule in 1997.

The announcement triggered an angry response as protesters took to the streets in several parts of the territory in the evening. Local media reported fires being set at multiple locations and riot police responding with tear gas.

A 14-year-old boy was shot in the thigh as a police officer opened fire while encircled by protesters in the New Territories, according to local media. He was taken to hospital and reportedly remains conscious.

Government leader Carrie Lam told a press conference earlier that protesters will be banned from wearing masks or any other face-covering material that makes it hard for police to identify them.

"It is a difficult decision but also a necessary one for public interest," Lam said. "We are now in rather extensive and serious public danger. It is essential for us to stop violence and restore calmness in society as soon as possible."

She added that the new law will create a deterrent effect against violent protesters and rioters and will assist the police in law enforcement efforts.

Lam said that although she is invoking an emergency law, the former British colony is not in a state of emergency, nor is it entering one.

Since the protests started in June over a now-suspended China extradition bill, many protesters have worn surgical masks or air-filtering masks to protect themselves from teargas and pepper spray used by police and to maintain anonymity.

"I am very angry that the government has now resorted to invoking the emergency law to persecute us," said Iris Hau, a 22-year-old clerk. "The fear of not knowing what will happen next is most worrisome."

By nightfall, protesters continued rallying in various districts across the territory, blocking roads and vandalizing and setting fire to subway stations. Police responded by firing teargas while dispersing the crowds.

Also in the New Territories, a Bank of China branch was broken into and vandalized by masked protesters, according to local reports.

Justice Secretary Teresa Cheng said the ban would help prevent radicals from avoiding consequences for breaking the law.

"The measure will not affect the principles of free speech and freedom of assembly for the people as they can continue to freely take part in lawful and peaceful public events without wearing disguises," Cheng said.

"Considering the violent behavior in the past few months, we believe the measure's intrusion of people's rights and freedoms was appropriate," she said.

The law carries a maximum penalty of one-year imprisonment and a fine of HK$25,000 ($3,200), and a prison term of six months and fine of HK$10,000 for resisting police requests to remove a mask.

The subsidiary legislation will be tabled at the legislature for members' discussion, Lam said.

Joshua Rosenzweig, head of Amnesty International's East Asia Regional Office, denounced the legislation and called it an attempt to deter protesters.

"The Hong Kong authorities should not use emergency rules as a smokescreen for further tightening restrictions on protesters. We reiterate our call for the Hong Kong authorities to respect protesters' rights to peacefully express their opinions and to refrain from using excessive and blanket powers to silence them," he said.

Mass protests against the extradition bill, which would have allowed the transfer of fugitives to mainland China, have continued despite the government's announcement last month that the measure will be formally withdrawn in October.

British Foreign Secretary Dominic Raab on Friday urged the government to engage in political dialogue to resolve the situation.

"While governments need to ensure the security and safety of their people, they must avoid aggravating and instead reduce tensions," Raab said in a statement.


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