Police in Hong Kong are stepping up security measures on Friday, the first anniversary of Beijing's 1989 crackdown on pro-democracy activists after a new national security law took effect in the territory last year.
Public debate on the Tiananmen incident has been taboo in mainland China, but a civic group in Hong Kong had been allowed to hold an annual vigil because of the "one country, two systems" framework.
But Hong Kong police banned this year's event, citing the coronavirus pandemic. It was the second straight year that the vigil had not been permitted.
Police have repeatedly warned people against participating in the memorial, saying they will strictly deal with illegal assemblies.
Local media say police plan to deploy about 7,000 personnel across Hong Kong to enforce bans on gathering. And tight security will be in place Friday evening when the vigil was originally planned.
There are calls on social media for people to remember the victims in their own way, or to wear black to express their feelings.