A new national security law came into force in Hong Kong on Saturday despite growing international criticism that it could erode freedoms in the city, which is ruled by China but has some autonomy stemming from its history as a British colony.
The law took effect at midnight when it was published on a government website, days after Hong Kong's pro-Beijing lawmakers passed it unanimously, fast-tracking legislation to plug what authorities called national security loopholes.
Hong Kong Chief Executive John Lee signed the new national security law on Friday evening saying it "accomplished a historic mission, living up to the trust placed in us by the Central (Chinese) Authorities". Australia and Britain on Friday criticised China for its actions in Hong Kong after a meeting in Adelaide, noting in a joint statement "deep concerns about the continuing systemic erosion of autonomy, freedoms and rights".
Australia and Taiwan updated their travel advisories for Hong Kong, urging citizens to exercise caution.
"You could break the laws without intending to and be detained without charge and denied access to a lawyer," the Australian government said.
Hong Kong authorities, however, in a statement, "strongly condemned such political manoeuvres with skewed, fact-twisting, scaremongering and panic-spreading remarks".
Hong Kong returned to Chinese rule in 1997 with the guarantee that its high degree of autonomy and freedoms, including freedom of speech and of assembly, would be protected under a "one country, two systems" formula.
The United Nations and the European Union criticised the extremely swift passage of the law that was first tabled as a draft bill in early March.
"It is alarming that such consequential legislation was rushed through the legislature through an accelerated process, in spite of serious concerns raised about the incompatibility of many of its provisions with international human rights law," said the UN High Commissioner for Human Rights earlier.
The new law encompasses treason, espionage and external interference and is being closely watched by diplomats and businesses who fear they could further dent Hong Kong's allure as an international financial hub.
China and the Hong Kong government have defended the security crackdown as essential to restoring order after months of sometimes violent anti-government street protests in 2019.
In recent years, many pro-democracy politicians and activists have been jailed or gone into exile, and liberal media outlets and civil society groups have been shut down.
Some 291 people have been arrested for national security offences, with 174 of these and five companies charged so far according to official figures.
Chinese authorities insist all are equal before the national security laws that have restored stability to Hong Kong, and that individual rights are respected, though no freedoms are absolute.
A previous attempt to pass the national security law, called Article 23, was scrapped in 2003 after 500,000 people protested. This time round, public criticism has been muted amid the security crackdown.
Overseas Hong Kong people, however, are planning protests in Britain, Taiwan, Canada and Japan on Saturday.