Tuesday marked the 25th anniversary of Tiananmen Square protests, a democracy movement that has since been erased from history in China but is still remembered by people who witnessed the chaos that pervaded Beijing. What began as a relatively small student assembly in mid-April 1989 swelled to more than a million, and ordinary citizens went to the polls in droves to show their support for the demonstrators. China's government, which called the protests a "counter-revolutionary rebellion," imposed martial law and mobilized more than 200,000 troops in the capital. On June 4th, 1989, students gathered in Tiananmen Square, a vast public square in the heart of the capital, to demand democracy, human rights and a return to democracy for the Chinese people. The Beijing Public Security Bureau released the following statement: "Army tanks rolled into Tiananmen Square and crushed the student protest movement there on June 4, 1989. Among the most wanted was Xiaomei Zhongxing, a former PLA soldier who said he had never been shot, but still haunted by memories of when the tanks rolled into Tianenmen Park on the night of June 3 and the day after. Up to 1 million people occupied the square, making it the largest public square in the world at the time and one of the most popular in China. On June 4, 1989, Chinese troops entered the square and fired on civilians, and again the next day, June 5. That year, the protests ended for the first time when the government sent troops to shoot at students, activists and other people demonstrating against the Communist Party. The Chinese government began to exercise control over information that people can access online, such as social media and the Internet. Censorship appears to have intensified in recent months, potentially affecting the flow of information to and from social media such as Twitter, Facebook, and YouTube. A series of student protests have triggered hunger strikes, inspiring other similar strikes and protests across China. Some Chinese government leaders sympathize with the protesters "concerns, while others see them as a political threat. The Chinese government has become increasingly uncomfortable with the movement's growth, disrupting the daily lives of many young people in the country and government officials. Massive protests have taken place in cities across China, including Shanghai, although Shanghai has remained peaceful during the protests. Demonstrations have focused on Tiananmen Square in Beijing, and a welcome ceremony for Gorbachev, originally scheduled for that day, has been held in other cities, though his visit has otherwise passed off without incident. After Hu's death on April 15, the movement lasted seven weeks until tanks cleared Tiananmen Square on June 4. In Beijing, a military response that resulted in the deaths of more than 1,000 people and the destruction of hundreds of buildings has left many civilians dead or injured. In the spring of 1989, thousands of Chinese soldiers marched into Beijing's Tiananmen Square and opened fire on unarmed demonstrators. Released reports and modern verifications show that the widespread horror of the crackdown in Beijing on 4 June 1989 may have caused up to a thousand deaths. The death toll ranges from 1,000 to 2,500 and hundreds of thousands of people were injured. Chinese activists, mostly students, occupied Beijing's largest city center to demand their civil rights. The demonstrations were triggered by public mourning in Tiananmen Square, which soon turned into protests across China. Chinese students and activists from across the country, as well as international human rights groups, gathered in Beijing to promote far-reaching political and economic reforms. But the students who took to the streets in Beijing lacked clear programmatic goals, even though they generally expressed a desire to redefine the communist regime's bourgeois identity. It is impossible to understand China today without understanding what happened on June 4, 1989, "said Zhang Zhiyong, a former student of Tiananmen Square who now teaches a course on Tiananmen at Harvard University. On June 3 and 4, 1989, 180,000 soldiers and armed police marched into Beijing's Tiananmen Square and crushed student protests demanding democratic reforms after the death of progressive Communist Party leaders. China has since taken its censorship campaign to the next level, according to several censors who spoke anonymously to Reuters and the Associated Press. Human rights censors told Reuters that China has introduced state-of-the-art artificial intelligence that scrubs closed versions of social media such as Facebook, Twitter and YouTube to detect dissent faster and more accurately than any human censor could ever. Pro-democracy demonstrators give soldiers a "V" sign of victory as they stand in front of Tiananmen Square in Beijing on June 3, 1989. Demonstrators stand in front of a burning armored personnel carrier that was set on fire during the suppression of a student protest in Beijing's Tiananshui district on June 4, 1990. Democracy protesters flee Changan Avenue as soldiers march in front of Tiananmen Square in Beijing on June 3, 1989. Dissident students call on soldiers to return home after crowds flooded central Beijing on June 3 in protest at the crackdown on student protests in Tiananmen Square.