A former nurse has been jailed for life for the murder of four patients and told he will serve a minimum of 30 years.

Staff nurse Colin Norris, 32, from Glasgow, killed the vulnerable women in 2002 by giving them massive doses of insulin while working at Leeds General Infirmary (LGI) and the city's St James's Hospital.

Norris was convicted of four counts of murder and one attempted murder following a lengthy trial at Newcastle Crown Court.

Following sentencing, Mr Justice Griffith Williams said: "You are, I have absolutely no doubt, a thoroughly evil and dangerous man."

He was described by West Yorkshire Police as "extremely arrogant".

Detectives said he showed no remorse for killing Doris Ludlam, 80, Bridget Bourke, 88, Irene Crookes, 79 and Ethel Hall, 86.

He also tried to kill Vera Wilby, 90, but she survived the coma which followed the unnecessary insulin injection.

Police began an investigation after Dr Emma Ward noticed in November 2002 that Mrs Hall had slipped into a hypoglycaemic coma despite not being a diabetic.

Blood tests showed she had insulin levels 12 times the norm, and she died three weeks later.

Detectives looked at other deaths on the wards from comas when Norris was working and after a lengthy investigation found that by the time Dr Ward raised her concerns, he had already killed three times, and failed with one attempt.

Detective Chief Superintendent Chris Gregg said Norris had been growing in confidence and only the vigilance of Dr Ward prevented his six-month murder spree from continuing.

The nearest the prosecution came to outlining a motive was to suggest that Norris disliked working with the elderly.

All his victims were frail after suffering from hip problems, and they could all be considered a burden to nursing staff.

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