Mass murderer

Mass murder (sometimes interchangeable with "mass destruction") is the act of murdering a number of people, typically simultaneously or over a relatively short period of time and in close geographic proximity. The FBI defines mass murder as murdering four or more persons during an event with no "cooling-off period" between the murders. A mass murder typically occurs in a single location where one or more people kill several others. Many acts of mass murder end with the perpetrator(s) dying by suicide or suicide by cop.

A mass murder may be committed by individuals or organizations whereas a spree killing is committed by one or two individuals. Mass murderers differ 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 people over long periods of time. Mass murder is the hypernym of genocide, which requires additional criteria.

Mass murder is also defined as the intentional and indiscriminate murder of a large number of people by government agents; for example, shooting unarmed protesters, throwing grenades into prison cells, and randomly executing civilians. The largest mass killings in history have been governmental attempts to exterminate entire groups or communities of people, often on the basis of ethnicity or religion because of dislike or intolerance. 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.

The concept of state-sponsored mass murder covers a range of potential killings. It is defined as the intentional and indiscriminate murder of a large number of people by government agents. Examples are shooting of unarmed protesters, lobbing of grenades into prison cells, and random execution of civilians. Other examples of state-sponsored mass murder include:

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