On 3-4 June 1989, hundreds - possibly thousands - of Chinese protesters were killed when their call for democracy on Beijing's Tiananmen Square was brutally crushed.
Here some of the people affected by the massacre describe their experiences to the BBC. Click on the quotes for full interviews in video and text.
Official | Bao Tong
Bao Tong was a senior Communist Party official with a reformist agenda. He was arrested shortly before the Tiananmen crackdown, and remains under house arrest.
Student leader | Wu'er Kaixi
Protest organiser Wu'er Kaixi fled China following the demonstration, and remains a political commentator and democracy activist.
Mother | Ding Zilin
Ding Zilin is one of hundreds of parents whose children were killed in the Tiananmen massacre.
Worker | Han Dongfang
Han Dongfang, a railway worker, became the spokesman for China's first autonomous workers' union, set up in the square on 19 May 1989.
Photographer | Jeff Widener
Jeff Widener took the image of the lone Tiananmen protester who stood in front of a convoy of tanks - probably the most iconic image of the crackdown.
Local resident | Anonymous
This eyewitness was in Beijing throughout the protests and saw many injured people. He is still afraid of speaking out about what he saw.
China's unofficial leader at the time, Deng Xiaoping, said the crackdown was necessary because the government was dealing with "a number of rebels" and people who were "the dregs of society". Click
to read a speech he made shortly after the massacre, explaining the government's actions.