The latest attempt by political extremists in the Hong Kong Special Administrative Region to revive the yearlong anti-government campaign, which had died down after the introduction of the national security law in the SAR on June 30, ended in failure on Sunday.

At least 289 participants were arrested for various offenses — including advocating separatism, violating the Public Order Ordinance and breaching social-distancing rules — after the Hong Kong police took prompt and decisive actions to crack down on their unauthorized assembly.

The national security law has started to bite, with unauthorized protests being scaled back, violence and vandalism having stopped, separatist groups having been disbanded, and colluders with external forces having either renounced their cause — at least ostensibly — or fled the city altogether. Nonetheless, there are still radical elements awaiting the chance to relaunch their anti-government campaign of disruption and violence.

The postponement of the Legislative Council election because of the recent spate of novel coronavirus infections, which was originally slated for Sunday, was seized on as such an opportunity. They couldn't let Sunday pass uneventfully, as they are in desperate need of rallying points if they are to advance their political agenda. Hence, the unlawful gatherings organized by the behind-the-scene plotters through social media channels under the pretense of protesting against the postponement of the election.

Sunday's assembly of hundreds of protesters in streets and malls, which greatly increased the risk of virus transmission and undermined the government's anti-pandemic efforts, posed a serious threat to Hong Kong residents' health. It was further evidence, if any were needed, since they have been relentlessly maneuvering to undermine the universal community testing program championed by the HKSAR government, that the radicals prioritize their political agenda over the well-being of society.

It is said that Pandora's box once opened cannot be closed. But the SAR cannot afford to not close the Pandora's box of political extremism, which has been opened by the demagogues who have been vigorously preaching toxic ideas such as "breaking the law to achieve justice". That is why both the central and HKSAR governments will not sit on their hands and will do their utmost to foil attempts to resurrect the yearlong violent anti-government campaign, which has caused incalculable damage to the city's economy and rule of law.

The Hong Kong police took prompt and decisive action to uphold the rule of law on Sunday, demonstrating that they will not tolerate any illegal act. The political extremists in the SAR had better heed the "zero tolerance" warning issued by the Liaison Office of the Central People's Government in the HKSAR and accept that the law will be applied to the letter with no flexibility.