Harold Shipman (1946-2004) was a British doctor who was convicted of murdering 15 of his patients and is believed to have killed as many as 250 people over a period of 25 years. He was
From Wikipedia
Harold Frederick Shipman, known to acquaintances as Fred Shipman, was an English doctor in general practice and serial killer. He is considered to be one of the most prolific serial killers in modern history, with an estimated 250 victims over roughly 30 years. On 31 January 2000, Shipman was convicted of murdering 15 patients under his care. He was sentenced to life imprisonment with a whole life order. On 13 January 2004, one day before his 58th birthday, Shipman hanged himself in his cell at HM Prison Wakefield, West Yorkshire.