Animal and Human Killers
Mary Bell: Child-killer Mary Bell throttled pigeons before strangling two young boys.
Ian Brady: The"Moors Murderer" abused animals as both a child and an adult.
David Mulcahy and John Duffy: As children, Mulcahy tortured a hedgehog while Duffy looked on. The pair later went on to rape and murder women across London and the Home Counties.
Thomas Hamilton: The Dunblane massacre perpetrator spent his youth squashing rabbits' heads beneath the wheels of his car. He later killed 16 children and a teacher.
Robert Thompson: This killer of toddler Jamie Bulger displayed a noted cruelty to companion animals.
Fred West: It is believed that West's desire to mutilate human corpses began when he worked in a slaughterhouse, butchering the corpses of animals.
Harold Jones: In the 1920's, Wales' Jones gained notoriety as a teenage sex killer. His attacks on girls were preceded by his pulling wings off baby birds.
John Taylor: In 2000, Taylor strangled 16-year-old Leanne Tiernan. Searching his house, detectives found a dog with his head smashed in. Taylor had enjoyed clubbing pheasants to death and stabbed a fox repeatedly while out poaching.
David Atkinson: This lance corporal killed Cambridge student Sally Geeson in 2005. He had previously been convicted of attacking swans.