HONG KONG - More than 50 politicians and activists were rounded up by the police on Wednesday (Jan 6) morning in a fresh wave of arrests under a sweeping national security law enacted six months ago.

Police said 53 individuals linked to unofficial primaries held in July last year, to choose candidates from the pan-democratic camp to run in the September Legislative Council (Legco) election, were hauled up for subversion, in an operation involving 1,000 officers.

Senior superintendent Steve Li, from the police force's national security department, said that 45 men and eight women aged between 23 and 64 were arrested.

Of these, six were picked up for allegedly organising the primaries while the rest were "so-called candidates".

Mr Li said the opposition's plan had breached Article 22 of the national security law, which covers attempts to subvert state power.

Among those nabbed was legal scholar Benny Tai, a convicted leader of the Occupy Central Movement in 2014 and co-organiser of the unofficial election last July.

The unofficial primary election, an idea of Mr Tai's, was meant to help the opposition bloc win a majority in the 70-seat Hong Kong legislature.

This would have enabled the opposition camp to block government proposals and mount pressure for democratic reforms.

Under Article 52 of the Basic Law or the city's mini Constitution, the chief executive must resign if he or she repeatedly fails to get a budget approved by the legislature.

The Legco election, now scheduled for September this year, was postponed for a year by Chief Executive Carrie Lam, who cited the severity of the pandemic as a key reason for the move.

Also picked up in the Wednesday sweep were former lawmakers Andrew Wan, Helena Wong, James To, Lam Cheuk Ting and Wu Chi Wai, as well as a younger crop of opposition voices, which included Ventus Lau, Tiffany Yuen and Gwyneth Ho.

A post on former Demosisto leader Joshua Wong's Facebook page said officers had raided his home as well. He is currently serving time for organising and inciting others to join a protest outside the police headquarters in 2019.

Local media reported that the police also turned up at the office of online media outlet Stand News, where officers had the editor-in-chief sign documents related to a national security investigation.

Empowered by the new national security law, the authorities have swooped in to arrest prominent pro-democracy activists including Wong and media tycoon Jimmy Lai, and disqualified some democratic lawmakers from running in the now-shelved Legco election.

The raids prompted activists such as Nathan Law to leave the island on a self-imposed exile.

Under the law, protest slogans and songs widely heard and seen during the unrest in 2019 have also been declared illegal.

When asked if the latest police action is meant to obliterate dissent in the city as some critics are arguing, political observer Lau Siu Kai did not answer directly.

Instead, he pointed out that the writing was on the wall - that those who breach the security law would be taken to task.

Mr Lau, vice-president of the Chinese Association of Hong Kong and Macau Studies - Beijing's top think-tank on Hong Kong - noted that the Hong Kong government had warned in July last year that the act of holding the unofficial primaries might be a violation of the national security law.

But he added that the warning fell on deaf ears.

"What the government is doing now is to strictly enforce the national security law, uphold the authority of the law and promote its deterrent effect.

"As the preponderant priority is to safeguard national security, other concerns are of lesser importance," Mr Lau said.

He added that a silver lining of the government's move is that it will "clarify and concretise" the meaning of the security law.

Opposition politicians, Mr Lau added, can now operate only within the framework of the Chinese Constitution, the Hong Kong Basic Law and the national security law.

Mrs Lam had previously warned that the unofficial primaries could amount to an act of "subversion", while the territory's Constitutional and Mainland Affairs Bureau said the government had received complaints that the polls could be aimed at "manipulating" the Legco elections.

In a Facebook post, Law, who had fled to Britain, called on people not to panic, saying the true aim of the government is to strike fear into residents so as to crush dissent and deter resistance.

He also called on the opposition to prepare themselves for a public-opinion war.

An observer who declined to be named for fear of retribution believes the latest move is meant to purge the entire opposition camp and not just past lawmakers but also the crop of younger, more vocal and more extreme opposition candidates who won the unofficial primaries.

In particular, the observer noted, the arrest of social worker and ethnic minority champion Jeffrey Andrews point to the fact that dissent will be obliterated and that no one viewed by the government as a threat to its stability would be spared.

Secretary for Security John Lee on Wednesday stressed that the mass arrests target "active elements who are suspected to have been involved in the crime of overthrowing or interfering or seriously destroying the Hong Kong government's legal execution of duties".

He tried to assure that those who voted in the so-called primary election are not the authorities' targets.

"The people involved are suspected of making use of what they call a 35+ plan and a 10-step mutual destruction scheme to some way paralyse the Hong Kong government.

"They aim to get 35 or more seats in the Legco through something they have organised as a primary so that once they have achieved their goal, they will veto, regardless of the actual content of the government budget, so as to create a situation in which the Chief Executive has to resign and the government stopped functioning," said Mr Lee.

He added that the suspects concurrently have a 10-step mutual disruption plan in which they mobilise large-scale riots to paralyse society.

"Coupled with international sanctions, the plan is to create mutual destruction...will result in serious damage to society as a whole.

"That is why police action today is necessary," the Security Secretary said.

The city's pro-Beijing lawmakers have welcomed the operation, saying the primaries, part of plans to force the chief executive to resign, create a vacuum in parliament and overthrow sovereignty, was a clear violation of the security law.

In a move that could add to tensions between the United States and China, US citizen and lawyer John Clancey, who served as treasurer for the organisers of the primaries, is among those arrested.

He works at law firm Ho Tse Wai & Partners, which handled hundreds of protest cases.

Already, US President-elect Joe Biden's long-time aide and his pick for Secretary of State, Mr Antony Blinken, on Twitter called the sweeping arrests of pro-democracy demonstrators "an assault on those bravely advocating for universal rights".

He declared that the Biden-Harris administration will stand with the people of Hong Kong and against Beijing's crackdown on democracy.

On Wednesday, Beijing defended the arrest as a necessary measure to stop "external forces and individuals" colluding to undermine China.

The only damage was to "the kind of freedom of some external forces and individuals in Hong Kong to collude with each other to attempt to undermine China's stability and security", said foreign ministry spokesman Hua Chunying at a regular press briefing in Beijing.

Taiwan has weighed in on the mass arrests with the Mainland Affairs Council describing the move as shocking.

"The Hong Kong version of the national security law has frequently struck at democrats on charges of subverting state power.

"It not only highlights the fact that the Hong Kong Basic Law meant to protect the rights of Hong Kong people has become nothing but words, but its evil deeds have also turned Hong Kong from the 'Pearl of the Orient' into a shocking 'Purgatory of the Orient'," the Council said in a statement.