Pro-democracy leader Nathan Law leaves Hong Kong

Prominent Hong Kong democracy activist Nathan Law has left the city for an undisclosed location, he revealed on his Facebook page after testifying to a U.S. congressional hearing about a tough national security law China had imposed on the semi-autonomous region.

In a post late Thursday, he said that he had decided to advocate for Hong Kong internationally and had left the city.

"As a global-facing activist, the choices I have are stark: to stay silent from now on, or to keep engaging in private diplomacy so I can warn the world of the threat of Chinese authoritarian expansion," he said. "I made the decision when I agreed to testify before the U.S. Congress."

Law told reporters in a WhatsApp message that he would not reveal his whereabouts and situation based on a "risk assessment."

His departure comes two days after the national security law took effect, targeting secessionist, subversive and terrorist acts, as well as any collusion with foreign forces intervening in city affairs.

The Hong Kong government said in a statement Thursday night that popular protest slogan, "Liberate Hong Kong, the revolution of our times," connotes a call for Hong Kong's independence or its separation from China, meaning those using it or displaying it on flags or signs could be in violation of the new law.

WATCH |Facing 'stark' choices,Hong Kong democracy activist Nathan Law flees city:

Facing 'stark' choices, leading Hong Kong democracy activist Nathan Law flees city

4 years ago

Duration 2:09

'I think the future's grim,' Law said, but noted he will continue to voice Hong Kongers' demands for democracy.

Police arrested some 370 people Wednesday, 10 of whom were detained on suspicion of violating the national security law, when thousands took to the streets to protest it.

In some cases, suspects were found to be carrying paraphernalia advocating Hong Kong's independence, police said.

"Under this legislation Beijing just passed about 24 hours ago, anyone who would dare to speak up would likely face imprisonment once Beijing targeted you," Law told a congressional hearing via video link Wednesday. "So much is now lost in the city I love: the freedom to tell the truth."

Pro-democracy group dissolves

Law, 26, rose to prominence in Hong Kong as one of the student leaders of the pro-democracy Umbrella Revolution in 2014. In 2016, he became the youngest lawmaker elected to the city's legislature but was later disqualified after he raised his tone while swearing allegiance to China during the oath, making it sound like a question.

He was a leader of pro-democracy group Demosisto, with fellow activists Joshua Wong and Agnes Chow. All three resigned Tuesday ahead of the national security law coming into effect. With the loss of its top members, Demosisto dissolved.

Critics say the law effectively ends the "one country, two systems" framework under which the city was promised a high degree of autonomy when it reverted from British to Chinese rule in 1997.

Police arrested about 370 people Wednesday, including 10 on suspicion of violating the security law, as thousands took to the streets to protest the legislation. In some cases, suspects were carrying items advocating Hong Kong's independence, police said.

"That is blatantly eradicating 'one country, two systems.' It's blatantly putting the last nail in the coffin," Law said.

He urged the international community to prioritize human rights over trade interests, and to present a united front to "combat or contain the authoritarian expansion of China."

The maximum punishment for serious offences is life imprisonment, and suspects in certain cases may be sent to trial on the mainland if Beijing deems it has jurisdiction.

WATCH |Hundreds arrested in first hours of Hong Kong's new security law:

Hundreds arrested in first hours of Hong Kong's new security law

4 years ago

Duration 3:58

Hong Kong police made their first arrests under a new security law Wednesday. In a statement on Facebook, police said they arrested 300 people.

A 24-year-old man who was arrested for allegedly stabbing a police officer during protests on Wednesday has been charged with wounding with intent, police said Friday. He was arrested on board a plane to London, apparently trying to flee the region.

Police wouldn't say if the man would face additional charges under the security law.

A 23-year-old man was also charged with incitement to secession and terrorist activities on Friday, making him the first person to be prosecuted under the new law. Tong Ying-kit is accused of crashing a motorcycle into a group of police during Wednesday's protests while possessing a flag with the newly banned slogan.

UN'alarmed' at arrests

Separately, the UNhuman rights office voiced concern on Friday that "vague and overly broad" provisions in the law may lead to activists being prosecuted in violation of fundamental freedoms of assembly and expression.

"We are alarmed that arrests are already being made under the law with immediate effect, when there is not full information and understanding of the scope of the offences," UNhuman rights spokesperson Rupert Colville said.

"We are concerned that the definition of some of the offences contained in the law are vague and overly broad and do not adequately distinguish between violent and non-violent acts. This may lead to discriminatory or arbitrary interpretation and enforcement of the law, which could undermine human rights protection."

The offence of "collusion with a foreign country or with external elements" could leave activists open to prosecution for exercising their rights to freedom of expression, association and peaceful assembly, he said.

The law's provisions guaranteeing the presumption of innocence and rights to due process and fair trial must be upheld, in line with international treaties protecting civil and political rights, he said.