A bloody crackdown shook the world 25 years ago when Chinese security forces cleared out Tiananmen Square of student protesters during the early hours of the morning of June 4, 1989.
Reporting from Beijing at the time, New York Times journalist Nick Kristof described the bloody scene, where "tens of thousands" of troops stormed the square, in the process reclaiming it from the pro-democracy protesters, killing "scores of students and workers and wounding hundreds more as they fired submachine guns at crowds of people who tried to resist."
The protests first began in April 1989, with students filling Beijing's large, central square, to peacefully call for reform. The weeks that followed saw the arrest of thousands, violent clashes between student protesters and security forces and a disputed death toll, which was estimated to be between 500 and 2,600.
While the iconic image of an unarmed man standing before a row of tanks on a road leading to Tiananmen Square stays firmly planted in the world's collective memory, Chinese authorities have gone to great lengths to scrub the protests, the massacre and that scene from its history.
Days before the anniversary, Beijing police arrested Pu Zhiqiang, a well-known rights lawyer who has defended renowned artist Ai Weiwei, in order to discourage protests in honor of the massacre's anniversary.
That chill, of course, extends to the Internet. In the time leading up to the massacre's anniversary, the country's censors are hard at work. According to Oiwan Lamat of Global Voices, "The most frequently used and censored term on China's web is 'June 4,' the day the massacre took place. A number of other terms, like 'Hu Yaobang,' 'narrow,' 'rejected' and 'Mirror Magazine,' all of which are associated with the memoir of Deng Liqun on Hu Yuibang, have also been deleted. Keywords related to Hong Kong's politics are also being blocked."
While the exact details of the massacre are disputed, there is no doubt that the tragedy is surrounded by many unanswered questions.
Here are 13 photos of the protests and massacre that rocked China a quarter of a century ago: