Proponents of free press have described the arrest of Hong Kong pro-democracy media mogul Jimmy Lai and the raid of his newspaper offices as part of a deepening crackdown on dissent in the Chinese city as "outrageous" and "horrible".
Mr Lai was among seven arrested in an operation focused on his Next Media publishing group, the latest to target dissidents since Beijing imposed the new national security law on Hong Kong at the end of June, sending a political chill through the semi-autonomous city.
"They arrested him at his house at about 7am," Mark Simon, a close aide of Mr Lai's, told AFP, adding that the six other colleagues had also been arrested.
In a statement, police said seven people were detained on suspicion of colluding with foreign forces, one of the new national security offences, and fraud.
Journalists working at Mr Lai's Apple Daily newspaper took to Facebook to broadcast dramatic images of police officers conducting the raid.
In the footage the newspaper's chief editor Law Wai-kwong can be seen demanding a warrant from officers.
"Tell your colleagues to keep their hands off until our lawyers check the warrant," Mr Law was filmed saying.
Apple's staff were ordered to leave their seats and line up so police could check their identities as officers conducted searches across the newsroom.
At one point 72-year-old Mr Lai was present, in handcuffs and surrounded by officers.
In a statement police said the search was conducted with a court warrant, which they said was shown to staff.
Loathed by Beijing
The security law was introduced in a bid to quell last year's huge and often violent pro-democracy protests, and authorities have since wielded their new powers to pursue the city's democracy camp, sparking criticism from western nations and sanctions from the United States.
Mr Lai's Apple Daily and Next Magazine are unapologetically pro-democracy and critical of Beijing.
Few Hong Kongers generate the level of personal vitriol from Beijing that Mr Lai does.
For many residents of the city he is an unlikely hero, a pugnacious, self-made tabloid owner and the only tycoon willing to criticise Beijing.
"The search is horrible, I believe many journalists wouldn't expect this," Hong Kong Journalists Association chairman Chris Yeung told reporters.
Lai was arrested Monday on suspicion of collusion with foreign powers in the highest-profile use yet of the new national security law Source: AP
"I think somewhere in third-world countries there has been such kind of press freedom suppression, just didn't expect it to be in Hong Kong."
"The public searches of the media offices have had a shocking effect on the industry ... freedom of the press and expression are at stake," the Hong Kong Democratic Party said in a Facebook post.
The UN human rights office voiced deep concern at the arrest of Mr Lai and others under the new security law and urged authorities to ensure that the legislation is not being misused.
Jeremy Laurence, spokesman for the office of UN High Commissioner for Human Rights Michelle Bachelet, said in an email reply to Reuters: "We urge the authorities to review these cases to ensure that the arrests do not impinge on the exercise of rights protected by the international human rights law and Hong Kong's Basic Law.
"We repeat our calls for the authorities to monitor and review the operation of the security law and to amend it if necessary to ensure there is no scope for its misuse to restrict human rights guaranteed by international law and the Basic Law of Hong Kong," he said.
Mr Lai also received support from Taiwan Premier Su Tseng-chang.
"China should not treat Hong Kong this way. Taiwan is paying very close attention to the situation in Hong Kong and cares about the people of Hong Kong," Mr Su told reporters in Taipei.
"We still urge the Chinese government to keep its promise and respect Hong Kong's democracy and freedom."
Steven Butler, Asia program coordinator of the Committee to Protect Journalists, said Mr Lai's arrest "bears out the worst fears that Hong Kong's national security law would be used to suppress critical pro-democracy opinion and restrict press freedom."
Mr Butler called for Mr Lai to be "released at once and any charges dropped".
Wang Dan, dissident and exiled student leader of the crushed 1989 Tiananmen Square protests, described Mr Lai's arrest was "expected" but "still very outrageous because his two sons were also arrested, which was obviously an attempt by the authorities to destroy Lai's will through family ties", Mr Wang said on Twitter.
"I call on the international community to take immediate action."
But in China's state media, Mr Lai is a "traitor", the biggest "black hand" behind last year's protests and the head of a new "Gang of Four" conspiring with foreign nations to undermine the motherland.
Allegations of Mr Lai colluding with foreigners went into overdrive in state media last year when he met with US Secretary of State Mike Pompeo and Vice President Mike Pence.
'Prepared for prison'
Mr Lai spoke to AFP in mid-June, two weeks before the new security law was imposed on Hong Kong.
"I'm prepared for prison," he said. "If it comes, I will have the opportunity to read books I haven't read. The only thing I can do is to be positive."
He brushed off the collusion allegations, saying Hong Kongers had a right to meet with foreign politicians.
His life is a rags-to-riches story.
He arrived in Hong Kong aged 12 fleeing communist China.
If Mr Lai is charged with foreign collusion offences, he could face up to life in prison. Source: AAP
Mr Lai toiled in sweatshops, taught himself English and eventually founded the hugely successful Giordano clothing empire.
Beijing's deadly 1989 crackdown on pro-democracy students in Tiananmen Square turned him political and he became one of the few tycoons in Hong Kong willing to criticise China.
Authorities started shutting down his clothing empire on the mainland, so he sold it and turned to publishing raucous tabloids instead.
In the June interview with AFP, Mr Lai described Beijing's new security law as "a death knell for Hong Kong" and said he feared authorities would come after his journalists.
The law targets secession, subversion, terrorism and colluding with foreign forces.
Both China and Hong Kong have said it will not affect freedoms and only targets a minority.
But its broadly-worded provisions criminalise certain political speech overnight, such as advocating for sanctions, greater autonomy or independence for Hong Kong.
Critics, including many Western nations, believe the law has ended the key liberties and autonomy that Beijing promised Hong Kong could keep after its 1997 handover by Britain.
Its rollout has been combined with ramped-up police action against democracy supporters.
About two dozen, including Mr Lai, have been charged for defying a police ban to attend a Tiananmen remembrance vigil in early June.
Mr Lai and many others are also being prosecuted for taking part in last year's protests.
Last month a dozen high-profile pro-democracy figures were disqualified from standing in local elections for holding unacceptable political views.
The banned opinions included being critical of the security law and campaigning to win a majority in the city's partially-elected legislature in order to block government laws.
Shortly after the disqualifications, city leader Carrie Lam postponed the elections for a year, citing a surge in coronavirus cases.
