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.