Bloody May Day (血のメーデー事件, Chi no mēdē jiken) refers to a violent conflict that took place between protesters and police officers in the Kokyo Gaien National Garden in front of the Imperial Palace in Tokyo, Japan, on May 1, 1952. When a large crowd protesting the U.S.—Japan Security Treaty refused to disband, a bloody melee took place between protesters and police officers. Eventually the police officers opened fire on the crowd, killing 2 and injuring 22 with bullet wounds. Altogether, around 2,300 people (1,500 protesters and 800 police officers) were injured in the fighting.