Serial Killer

A serial killer is a person who murders three or more people over a period of more than 30 days, with a "cooling off" period between each murder, and whose motivation for killing is largely based onpsychological gratification. Often, a sexual element is involved with the killings. The murders may have been attempted or completed in a similar fashion and the victims may have had something in common; for example, occupation, race, appearance, sex, or age group.