A Hong Kong political group on Sunday said four of its members were warned by national security police not to join a planned women’s rights demonstration a day before the organisers announced it was cancelled.

Opposition group the League of Social Democrats said on its Facebook page its members were questioned on Friday by national security police and told not to join the authorised Sunday march, which was called off on Saturday.

The league said that the right to protest was guaranteed under the Basic Law, the city’s mini-constitution, but it was being infringed.

“Freedom of speech is threatened, and the right to march is trampled on,” the party said.

Police officers on patrol in Wan Chai near Southorn Playground, the muster point for a women’s rights event organised by the Hong Kong Women Workers’ Association and scheduled for Sunday, but called off on Saturday.

The event would have been the first authorised rally in Hong Kong in three years, as the government banned large public gatherings due to the Covid-19 pandemic, a rule lifted in December.

A strong police presence was seen at the proposed Wan Chai starting point of the march after the force on Saturday night said groups intent on violence had signalled an intention to take part.

Dozens of police were stationed around Wan Chai MTR station exits near Southorn Playground, the march’s planned muster point, or on patrol in the area.

But by 11am, the time scheduled for the start of the event, there were no activists to be seen.

The Hong Kong Women Workers’ Association planned the demonstration in support of International Women’s Day on Wednesday.

The association said it regretted the cancellation, but gave no explanation why the decision was taken.

The association later told the Post it had no further comment.

In response to the statement from the league, a police spokesman said: “Any action taken by the police will be dealt with according to the actual situation and according to law.”

The association was given a letter of no objection from police after it asked permission to hold the event.

Acting Senior Superintendent Dennis Cheng Wai-kin, of the Hong Kong Island police regional headquarters, said after the cancellation that police had found many people, including violent gangs, had indicated they would attend.

Cheng added the force respected the decision by the organisers and that the association had “struck a balance of different factors”.

He also warned anyone who planned to gather at the playground that they could be prosecuted for taking part in an unauthorised assembly.

Another large scale event, however, was held without incident on Sunday in Aberdeen.

The Tin Wan Kai-Fong Federal Association and the Kowloon City District Recreation and Sports Council celebrated the birthday of Guanyin, the Goddess of Mercy.

One of the organisers Amy So Yuek-mei, co-owner of the Lotus Buddha House, said about 300 people attended what had been an annual event, but suspended since 2019 because of that year’s social unrest and the later Covid-19 pandemic.

So also said the police had not given any instructions to them on mask wearing, a point left unresolved after the outbreak of Covid-19 pandemic forced the government to impose mandatory use of masks.

The government banned protesters from using face coverings after many demonstrators did so during the anti-government protests in 2019.

The ban covered authorised public meetings and demonstrations as well as those that did not have official sanction. Offenders can be hit with a one-year jail sentence and a maximum fine of HK$25,000 (US$3,185).

The anti-coronavirus mask restriction was lifted last Wednesday.

“I think some of us in the parade were still with their masks on but everything just looked normal. No police officers were picking on us with masks at all,” So said.

Chief Executive John Lee Ka-chiu said the mask mandate on health grounds and the ban on wearing them at demonstrations were different situations and the block on them for protests would be reviewed later.

Protests have been held in Hong Kong on a regular basis over the past few decades, but rarely since the Beijing-imposed national security law came into force in 2020.

Louise Ho Pui-shan, the commissioner for customs and excise, said in a television interview on Sunday that the service’s frontline staff had heightened their alertness to prevent materials that could endanger national security from entering the city.

She added nothing of concern had been detected yet.

“The overall situation in Hong Kong society is stable, but we must guard against the infiltration of the consciousness that endangers the country,” Ho said.