John Leonard Orr is an American convicted serial arsonist, mass murderer and
former firefighter. A fire captain and arson investigator in Glendale, California, Orr was convicted of serial arson and four counts of murder; he is believed to have set nearly 2,000 fires in a 30 year arson spree, most of them between 1984 and 1991, making him the most prolific serial arsonist in American history. From Wikipedia
