A former nurse, dubbed the "Angel of Death", has failed in his attempt to overturn four murder convictions at the Court of Appeal.

Colin Campbell, previously known as Colin Norris, was sentenced to life imprisonment in 2008 for killing Doris Ludlam, Bridget Bourke, Irene Crookes and Ethel Hall.

The victims were all orthopaedic ward patients at Leeds hospitals in 2002 who died after developing severe, unexplained hypoglycaemia.

Three appeal court judges dismissed Campbell's challenge on Thursday, with Lady Justice Macur, Justice Picken and Sir Stephen Irwin stating: "We have no doubt about the safety of any of the five convictions. The appeals are dismissed."

Colin Campbell, formerly known as Colin Norris, was jailed for life in 2008 for the murders of four elderly patients and attempting to murder a fifth

Campbell had also been convicted of attempting to murder a fifth patient.

He has consistently denied any wrongdoing, maintaining he did nothing to cause hypoglycaemia in any of the patients.

The case was referred to the Court of Appeal by the Criminal Cases Review Commission (CCRC) in 2021, which had previously described the prosecution's evidence as "wholly circumstantial".

Campbell's conviction followed a five-month trial at Newcastle Crown Court in 2008, where 20 experts gave evidence.

The victims were all orthopaedic ward patients at Leeds hospitals in 2002 who died after developing severe, unexplained hypoglycaemia

During a 14-day hearing earlier this year, Campbell's legal team argued that new expert knowledge rendered the convictions unsafe.

The Crown Prosecution Service countered that much of the evidence presented had already been heard by the jury at the original trial.

Michael Mansfield KC, representing Campbell, told the appeals hearing that four similar cases of patients suffering "sudden and profound" hypoglycaemia had been identified at Leeds teaching hospitals between January 2003 and August 2005.

He unsuccessfully appealed against his conviction in 2009 and subsequently applied to the CCRC in 2011.

Three appeal court judges dismissed Campbell's challenge on Thursday

He noted the "remarkably similar" ages of all nine cases, with patients aged between 78 and 93, arguing this "was not discussed" at trial.

However, the judges rejected this argument, stating: "On our own analysis, the 'extra' cases serve to underline rather than undermine this aspect of the phenomena that are said to be distinctive in those cases of administration of exogenous insulin."

James Curtis KC, for the Crown Prosecution Service, argued there was "very little evidence of any sudden and severe hypoglycaemia when it is caused naturally".

The judges concluded that expert evidence suggesting the women may have died from natural causes was "inconsistent with, and fails to address the phenomena evidenced" in the patients.