Quote:Hong Kong closed off a park where tens of thousands gather annually to commemorate China’s 1989 Tiananmen crackdown and arrested the vigil’s organiser, in what activists see as suppression of one of the city’s main symbols of democratic hope.

Thousands of officers are expected to patrol the city's streets on Friday to prevent gatherings of people lighting candles for the pro-democracy protesters killed by Chinese troops in Beijing 32 years ago.

The heightened vigilance from authorities was a marked departure from Hong Kong's cherished freedoms of speech and assembly, bringing the global financial hub closer in line with mainland China's strict controls on society, activists say.

Hong Kong's annual June 4 vigil, the world's largest, usually held in Victoria Park, is widely seen as a symbol of the former British colony's democratic aspirations and desire to preserve its different way of life from mainland China.

Early on Friday, police arrested Chow Hang Tung, vice-chairwoman of the Hong Kong Alliance in Support of Patriotic Democratic Movements of China, for promoting an unauthorised assembly. Hours later, officers cordoned off most of the downtown park.