Hong Kong's leader, Carrie Lam, said this week that any events to commemorate those killed in the 1989 crackdown would be subject to national security laws.
In the Hong Kong's Victoria Park, where people had come together for an annual vigil before the Covid-19 pandemic hit, authorities blocked off main parts of the venue and warned residents against illegal gatherings.
Hundreds of police, some with sniffer dogs, patrolled the park area and conducted stop-and-search checks. As night fell, floodlights lit up an empty expanse of football pitches.
The last time the vigil was held in Hong Kong, in 2019, more than 180,000 people attended, according to organiser estimates, filling six football fields.
"Everyone is remaining silent because they are terrified of getting arrested," Hong Kong resident Victor, 57, who asked to be identified only by his first name, said inside the park.
China imposed a national security law on Hong Kong in June 2020 punishing acts of subversion, terrorism and collusion with foreign forces with up to life in prison. Beijing said the law was necessary to restore stability after anti-government protests in 2019.
'TO REMEMBER IS TO RESIST'
Since the legislation was imposed, people or organisations affiliated with the sensitive June 4 date and events to mark it have been targeted by Hong Kong authorities.
Hong Kong has banned the annual vigil since 2020, citing coronavirus restrictions. Some democracy campaigners accuse authorities of using those rules to suppress activism, a claim that officials reject.
Last year, police blocked off the Hong Kong park to prevent people gathering to commemorate the anniversary and arrested the planned vigil's organiser.
"To remember is to resist," prominent Chinese human rights lawyer Teng Biao told Reuters from the United States. "If nobody remembers, the suffering of the people will never stop and the perpetrators will continue their crimes with impunity."
In Chinese-claimed Taiwan, President Tsai Ing-wen decried the "collective memory of June 4 being systematically erased in Hong Kong".
"But we believe that such brute force cannot erase people's memories," she posted on her Facebook and Instagram pages.
U.S. Secretary of State Antony Blinken called the Tiananmen crackdown "a brutal assault", adding in a statement: "The efforts of these brave individuals will not be forgotten".
Chinese Foreign Ministry spokesman Zhao Lijian, at a routine news conference on Thursday, reiterated Beijing's line on the events. "The Chinese government has long ago come to a clear conclusion about the political incident that happened in late 1980s," he said.