HONG KONG • Hong Kong's government said yesterday that 12 pro-democracy candidates had been disqualified from running for election to the legislature, citing opposition to a new national security law imposed by Beijing, but denied infringing civil rights.

Disqualified candidates included pro-democracy activist Joshua Wong, some members of the Civic Party, a moderate, old-guard opposition group, and others who won an unofficial "primary" vote by the opposition camp this month.

The government said there could be more disqualifications.

The move came less than 24 hours after four people were arrested for suspected offences under the security law. The back-to-back actions were seen as a sweeping gesture showing how much the national security law enacted last month had strengthened Beijing's hand.

Critics said the disqualification sought to curb the ascendancy of a young, more defiant generation of pro-democracy activists after an overwhelming win in last year's lower-level district council elections.

"Clearly, #Beijing shows a total disregard for the will of the #Hongkongers, tramples upon the city's last pillar of vanishing autonomy and attempts to keep #HK's legislature under its firm grip," Mr Wong tweeted.

Chances for a historic majority in the Legislative Council, or mini-Parliament, for the opposition camp will take a further blow if the government decides to postpone the Sept 6 vote, as expected, amid the coronavirus pandemic.

Hong Kong has disqualified candidates before, but not on this scale.

The disqualification of Civic Party candidates signals that Beijing is becoming less tolerant of even moderate democrats, who have for decades been a vocal opposition in the legislature.

"The government is constructing a CCP (Chinese Communist Party) assembly in Legco to eliminate most of the opposition voices. Outrageous," tweeted Mr Nathan Law, a pro-democracy activist and former lawmaker who was kicked out of the legislature. He fled Hong Kong for Britain earlier this month.

The Civic Party said its existence is not confined to the legislature, often referred to as the Legco, and it will continue to work for its values.

"When the regime wishes to enslave us, the best thing to do is to stand firm and tell the regime we would not change," said party member Kwok Ka-ki, who was among those disqualified.

The Hong Kong government said advocating self-determination, soliciting intervention by foreign governments, or "expressing an objection in principle" to the enactment of the new security law was behaviour that "could not genuinely" uphold the city's mini-Constitution, the Basic Law.

Candidates are required by law to pledge allegiance to Hong Kong and the Basic Law.

The government said there was "no question of any political censorship, restriction of the freedom of speech or deprivation of the right to stand for elections as alleged by some members of the community".

Beijing's top representative office in the city, the Hong Kong Liaison Office, said it supported the disqualifications as the candidates aimed to "paralyse the government" and "subvert state power".

Beijing introduced the security legislation to punish what it broadly defines as secession, subversion, terrorism and collusion with foreign forces in the former British colony.

Critics of the law say it erodes basic rights and freedoms, while supporters say it will bring stability after a year of often-violent anti-government and anti-China unrest.

Beijing says it was vital to plug national security loopholes left open by Hong Kong's inability to pass such legislation on its own, as required by the Basic Law.

Hong Kong's last British governor Chris Patten called the disqualifications an "outrageous political purge".

Late on Wednesday night, Hong Kong police said they arrested four people aged 16 to 21 for suspected offences under the new security law, the first such detentions outside of street protests.

The three men and a woman, all students, were suspected of being involved in an online group that pledged to use every means to fight for an independent Hong Kong.

Student Localism, a group that used to advocate independence, said its former leader Tony Chung, 19, was among those arrested. Two other former members were identified by local politicians and media.

REUTERS, BLOOMBERG, AGENCE FRANCE-PRESSE