For the past 34 years, the height of “ politically sensitive periods ” for the Chinese government invariably falls around the same day: June 4, the anniversary of the Tiananmen Square massacre in Beijing. And, as use of the internet has become increasingly ubiquitous in China, online surveillance and censorship go into overdrive during this period.

Police in Hong Kong have detained several pro-democracy activists on the anniversary of the Tiananmen Square massacre. Authorities have banned public commemoration of the 1989 incident, which saw China crush peaceful protests in Beijing with tanks and troops. However, candlelight vigils have been taking place in other cities worldwide.

With candlelight vigils to the victims of the 1989 crushed student uprising in Beijing now only a memory, the anniversary is also a reminder of the freedoms Hong Kong has lost.

Restrictions in Hong Kong have stifled what were once the largest vigils marking the anniversary of the bloody crackdown by Chinese troops on pro-democracy demonstrators.

China has tightened access to Tiananmen Square in central Beijing on the anniversary of 1989 pro-democracy protests. In Hong Kong, which had been the last Chinese-controlled territory to hold commemorations,

Hong Kong police have detained eight people on the eve of the 34th anniversary of China’s Tiananmen Square crackdown