ANGEL OF DEATH
Between February and April 1991, nurse Beverley Allitt (below), then 22, killed four children at Grantham and Kesteven Hospital, Lincolnshire, by insulin or potassium overdose, or injecting an air bubble into the bloodstream.
She tried to kill three others and caused grievous bodily harm to a further six. Those who died were Liam Taylor, 7 weeks, Timothy Hardwick, 11, Becky Phillips, 2 months, and Claire Peck, 15 months.
Allitt got 13 life sentences in 1993 and, in 2007, the High Court ruled she must serve a minimum of 30 years.