Harold Frederick ShipmanHarold Frederick Shipman, born June 14, 1946 (some sources: January 14, 1946), a British doctor, may be the most deadly serial killer in history. A report into his activities submitted in July 2002 confirmed he had killed 215 of his patients between 1975 and 1998. Dame Janet Smith, the judge who submitted the report, admitted that many more suspicious deaths could not be definitively ascribed to him. In total, 459 people died while under his care and many of the cases are shrouded in uncertainty because Shipman was often the only person to certify a death. Most of his victims were elderly women.
Shipman was convicted in January 2000 of killing 15 patients with lethal injections of diamorphine (the medical version of heroin, legal for pain control in the UK). He has been told he will never leave prison.
Shipman has never made any statements about his actions so his motives remain a mystery.