These murders generally produce the erroneous assumption that the offenders are insane. They also generate extensive publicity. The media has both beneficial and harmful effects on the investigation and processing of these cases and on the behavior of offenders, potential offenders, and others. The most common types of mass murderers are family annihilators, pseudocommandos, and killers who use bombs or other methods that permit their escape. Serial killers include psychopathic sexual sadists, crime spree killers, people working for organized criminal operations, poisoners and asphyxiators of people in their care, and supposed psychotics. Sensational homicides usually involve sadism, mutilation, the occult, prominent offenders and victims, or murders of children or parents. 10 references.