Mass Murder

Mass murder (in military contexts, sometimes interchangeable with "mass destruction" or "genocide") is the act of murdering a large number of people (four or more), typically at the same time or over a relatively short period of time. According to the FBI, mass murder is defined as four or more murders occurring during a particular event with no cooling-off period between the murders. A mass murder typically occurs in a single location in which a number of victims are killed by an individual or more. Most acts of mass murder end with the death of the perpetrator(s), whether by direct suicide or being killed by law enforcement.

A mass murder differs from a spree killing in that it may be committed by individuals or organizations alike, whereas a spree killing may only be committed by one or two individuals. Mass murder may also be defined as the intentional and indiscriminate murder of a large number of people by government agents. Examples are the shooting of unarmed protestors, the carpet bombing of cities, the lobbing of grenades into prison cells and the random execution of civilians. Mass murderers are different from spree killers, who kill at two or more locations with almost no time break between murders and are not defined by the number of victims, and serial killers, who may kill large numbers of people over long periods of time. The largest mass killings in history have been attempts to exterminate entire groups or communities of people, often on the basis of ethnicity or religion. Some of these mass murders have been found to be genocides and others to be crimes against humanity, but often such crimes have led to few or no convictions of any type.