The Chinese government still considers the 1989 protests a "counter-revolutionary riot", and public discussion of the student movement is taboo. But the military crackdown, which killed at least hundreds, is mourned openly every year in Hong Kong, a semi-autonomous Chinese territory that is promised Western-style civil liberties.
This year, however, Hong Kong democracy activists alleged that local police were trying to clamp down on their activities.
On Saturday, police officers arrested 13 activists and confiscated a "Goddess of Democracy" statue dedicated to the Tiananmen victims and set up next to a shopping mall. Police said the activists did not have a licence to display the statue.
The activists pressed ahead with a scheduled protest yesterday, displaying a smaller version of the statue. Police did not interfere with this protest.
"Political persecution is shameful," the 400 protesters chanted in the rain before setting off for Hong Kong's government headquarters.
"No matter how harsh the crackdown, we will persist until the end with a firm hand," veteran activist Szeto Wah told the crowd.
The activists plan to stage a candlelight vigil in the former British colony on Friday, the anniversary of the crackdown.