The demonstrators, seeking democratic reform, had been protesting in Tiananmen Square for seven weeks, refusing to move until their demands were met. The protest began with a march by students in memory of Hu Yaobang who had died a week before. Soon they were joined by millions of supporters, eager to show their anger at widespread corruption.
When peaceful attempts to persuade the demonstrators to leave failed, the government threat to do whatever it saw necessary to clamp down on 'social chaos' was carried out and the military offensive began.
The events in Tiananmen Square were described as the greatest challenge to the communist state in China since the 1949 revolution. It was suggested that the communist leader Deng Xaioping personally sanctioned the attack to shore up his leadership.
The precise number of dead may never be known but hundreds and possibly thousands perished in the slaughter.