HONG KONG, June 14, 2024 (BSS/AFP) - The United States and Australia expressed concern Friday over Hong Kong's invoking of a national security law to cancel the passports of six democracy activists, adding to a growing chorus of Western condemnation.

The Chinese finance hub in March passed the security law, colloquially known as Article 23, which expanded government powers beyond those granted by legislation Beijing imposed in 2020 to quell dissent.

On Wednesday, Hong Kong cancelled the passports of six activists who had fled to Britain -- citing the new law as the legal basis -- saying they were "lawless wanted criminals" who continued to endanger national security.

The United States on Friday called on Hong Kong officials to "immediately halt their efforts to intimidate and silence dissidents".

"The United States remains strongly concerned that Hong Kong authorities are attempting to assert recently enacted Article 23 legislation extraterritorially as part of their ongoing transnational repression efforts," a State Department spokesperson said.

Australia also said it was "concerned by the erosion of rights and freedoms", adding that the security laws had "far reaching impacts, including on individuals in Australia".

Their comments come a day after Anne-Marie Trevelyan, UK minister of state for the Indo-Pacific, called the passport cancellations the "latest regrettable decision from Hong Kong authorities".

"It is unacceptable to use these kinds of legal measures to try and punish freedom of expression in (Britain)," she wrote on social media platform X Thursday.

A European Union spokesperson said Thursday that the passport cancellations and other measures targeting the activists "seem to confirm our concerns about an extraterritorial application (of the security laws) to stifle dissent".

Canada also raised the alarm about the "law's broad definitions of national security offences" causing enforcement overreach.

"Canada deplores attempts by Hong Kong authorities to apply its national security legislation extraterritorially and will oppose any attempt to apply these laws within Canada," it said.

The six activists had already been targeted with HK$1 million ($128,000) bounties that Hong Kong issued last year, with authorities accusing them of committing national security crimes.

They are former lawmaker Nathan Law, veteran unionist Christopher Mung Siu-tat, and activists Finn Lau, Fok Ka-chi, Choi Ming-da and Simon Cheng.