The Viipuri massacre was the killing of approximately 360 to 420 Russians in the city of Viipuri during the Finnish Civil War in April–May 1918. The massacre took place during and after the Battle of Viipuri as the White Guards captured the city from the Red Guards. At least half of the victims were Russian soldiers and military personnel. The slain were mainly men and young boys, as young as 12-13 years old: nine out of ten were men fit for military service, according to Finnish propaganda. The White Guards were "cleansing" the city of Red Guards of whom 800 were slain; however, only a small minority of the killed Russians were affiliated with the Finnish labour movement.