Six days after the death of Hu Yaobang, the deposed reform-minded leader of the Chinese Communist Party, some 100,000 students gather at Beijing’s Tiananmen Square to commemorate Hu and voice their discontent with China’s authoritative communist government. The next day, an official memorial service for Hu Yaobang was held in Tiananmen’s Great Hall of the People, and student representatives carried a petition to the steps of the Great Hall, demanding to meet with Premier Li Peng. The Chinese government refused such a meeting, leading to a general boycott of Chinese universities across the country and widespread calls for democratic reforms.

READ MORE: Tiananmen Square Protests: Timeline & Massacre

Ignoring government warnings of violent suppression of any mass demonstration, students from more than 40 universities began a march to Tiananmen on April 27. The students were joined by workers, intellectuals, and civil servants, and by mid-May more than a million people filled the square, the site of communist leader’s Mao Zedong’s proclamation of the People’s Republic of China in 1949. On May 20, the government formally declared martial law in Beijing, and troops and tanks were called in to disperse the dissidents. However, large numbers of students and citizens blocked the army’s advance, and by May 23 government forces had pulled back to the outskirts of Beijing.

On June 3, with negotiations to end the protests stalled and calls for democratic reforms escalating, the troops received orders from the Chinese government to reclaim Tiananmen at all costs. By the end of the next day, Chinese troops had forcibly cleared Tiananmen Square and Beijing’s streets, killing hundreds of demonstrators and arresting thousands of protesters and other suspected dissidents. In the weeks after the government crackdown, an unknown number of dissidents were executed, and communist hard-liners took firm control of the country.

The international community was outraged at the incident, and economic sanctions imposed by the United States and other countries sent China’s economy into decline. However, by late 1990, international trade had resumed, thanks in part to China’s release of several hundred imprisoned dissidents.

READ MORE: Communism Timeline