Britain has accused China of using the new Hong Kong national security law as a "pretext to silence opposition" after the arrest of leading media tycoon and protester, Jimmy Lai.
Mr Lai's detention for suspected collusion with foreign forces is the highest profile arrest yet under the new law in Hong Kong, widely seen as a crackdown on the semi-autonomous city's freedoms by China.
Prime Minister Boris Johnson's spokesman said Britain was "deeply concerned" by the arrest, which also saw Mr Lai's newspaper's offices raided.
"This is further evidence that the national security law is being used as a pretext to silence opposition," he said. "The Hong Kong authorities must uphold the rights and freedoms of its people."
Around 10,000 people had earlier tuned in to watch a police raid on the office of Apple Daily, a Hong Kong tabloid published by Mr Lai’s media company, Next Digital.
Ryan Law, the editor-in-chief of Apple Daily, defied police warnings to stop filming as 200 officers streamed into the newspaper's headquarters, ignoring questions over what legal grounds they had for entering and removing plastic boxes as evidence.
Officers demanded the few employees there produce identity documents and register with police. Staff were seen standing by newsroom desks decorated with bright pro-democracy protest posters, including one reading: "Who's afraid of the truth!"
Among the others arrested were two of Mr Lai's sons, young pro-democracy activist Agnes Chow and Wilson Li, a former activist who describes himself as a freelance journalist working for Britain's ITV News.
Mr Lai, long an outspoken critic of Beijing, is the most prominent pro-democracy activist to be arrested so far under the national security law.
He is also a British citizen, and the first foreign national to be arrested under the new law, imposed by Beijing on Hong Kong, which punishes activities China considers subversion, secession, terrorism and foreign collusion, with up to life in prison.
As of this time the police are in the homes of Mr. Lai and his son executing search warrants.
Other members of the group have been detained or taken in for questioning. It’s a press scrum at Mr. Lai’s home now so info locally will come out.
— Mark Simon (@HKMarkSimon) August 10, 2020
On Friday, the US sanctioned 11 top officials, including city chief executive Carrie Lam, for their role in curtailing liberties in the Chinese territory.
China on Monday announced unspecified sanctions against 11 US politicians and heads of organizations promoting democratic causes, including Senators Marco Rubio and Ted Cruz, who have already been singled out by Beijing.
Foreign ministry spokesperson Zhao Lijian on Monday said those sanctioned had "performed badly" on issues concerning Hong Kong, where China has cracked down on opposition voices following its imposition of a national security law in the semi-autonomous southern Chinese city last month.
Benedict Rogers, co-founder of Hong Kong Watch, an advocacy group, said the arrest of Mr Lai plus the office raid “is one of the most brazen assaults on basic freedom of expression and freedom of the press since the national security law was imposed."
The move “sends the message that no one is safe in Hong Kong unless they stay completely silent,” he said. “In light of these arrests, I urge the United Kingdom and all democracies to follow the recent action by the United States and impose immediate targeted Magnitsky sanctions.”
Many have criticised the national security law for crushing freedoms in the semi-autonomous city, meant to be guaranteed for 50 years after the former British colony was returned to Beijing rule in 1997. Chinese authorities, however, have said the law is necessary to bring stability after mass protests roiled the city last year.
Before Monday, 15 others had been arrested under the new legislation. Although there haven’t been mass arrests as many feared, the imposition of the law itself has already spurred a number of changes in the city.
Prominent activists, like Joshua Wong, have stepped down from their positions in political parties, while others, like Nathan Law, have fled abroad including to the UK.
Many Hong Kong residents have also deleted social media posts or made their profiles private over fear that personal commentary online could be deemed as breaching the national security law.
Officers are seen examining staffers' desks inside Apple Daily's HQ, contradicting assurances from the National Security Department's Steve Li that journalistic materials would not be searched. Clip: Apple Daily via StandNews. In full: https://t.co/fJM6JmxV6n pic.twitter.com/JPLk7PuCAQ
— Hong Kong Free Press HKFP (@HongKongFP) August 10, 2020
Popular protest slogans and songs have also been declared illegal and banned at schools, while books have cleared off shelves in public libraries.
Over the weekend, Beijing made it illegal to fly the Chinese flag upside down in amendments to a separate law that bans activities deemed to desecrate the flag. Protesters have before set fire to the Chinese flag or thrown it into Hong Kong’s Victoria Harbour, acts the authorities deemed to disrespect the flag.
Chinese state media praised Mr Lai’s arrest on Monday, labelling him a “riot supporter” and “modern traitor,” and calling for severe punishment.
Mr Lai was already facing charges in Hong Kong, including for inciting others to participate in an unauthorised assembly last year during a string of mass protests that lasted for months.
As such, he hasn’t been allowed to leave Hong Kong – and told the Telegraph in July vowed he wouldn’t do so, even if he could.
“They send cars to follow me, to intimidate me, they have people telling me ‘it’s not just prison for life; you can be shot,’” he said.
“If I leave I would disgrace myself and undermine the democratic movement. I would be a fool to leave,” Mr Lai said. “I will be here in Hong Kong until the last day.”