 Because the victims were either very young or activists, it was apparent that this was not a gang shooting.A number of theories about the motivation for the crime appeared in the weeks afterward; that the attack was police retaliation for the killing of two police officers earlier that day, that the victims had been mistaken for a youth gang and killed by accident, or that the victims had been targeted because a number of them were activists.Later ballistics tests confirmed that the bullets used in the killings were those used by both the Colombian National Police and the Colombian Army.