Karen Rees - who asked us not to show her face after receiving abuse on social media - has been speaking exclusively to Emma Sweeney.
A former nursing chief has said she was not given enough information to be able to remove nurse Lucy Letby from a neonatal unit after it was claimed she refused to do so.
Karen Rees was the Head of Nursing at the Countess of Chester Hospital's urgent care division before she retired in March 2018.
Letby, 33, who murdered seven babies and tried to kill six more between 2015 and 2016, was told she would face the rest of her life behind bars when she was sentenced on Monday.
The hospital's neonatal unit Head Consultant, Dr Stephen Brearey, told Manchester Crown Court he had informed Ms Rees he and his colleagues were "not happy" with Letby because of the number of baby deaths and collapses during her shifts.
But, in her only sit-down interview, Ms Rees has told ITV Granada Reports there was not given enough information to justify removing Letby from her duties.
She says the former Nursing Chief said Karen Townsend, the Director of Urgent Care at the hospital, and Ravi Jayaram, a consultant who was the clinical lead for neonates and paediatrics, told her during a general review meeting that there were concerns about Letby's clinical practices.
Ms Rees said she was told at that stage Dr Brearey thought Letby should be removed from the neonatal unit.
She said she immediately went to find Mr Jayaram and Dr Brearey in order to obtain more information about the allegations but Dr Brearey was not in the office the two men shared.
Ms Rees said: "Ravi wouldn't give me any information to explain why Lucy Letby should be removed from the unit.
"He said nothing about air embolus, or over-feeding. He did not even mention babies dying and Lucy Letby being present. He just asked for Lucy Letby to be removed from the NNU (neo-natal unit)."
Ms Rees said she felt she "urgently" needed to speak with Dr Brearey about concerns around Letby.
She added that, after she got hold of him, she explained that she needed more information before she could remove a nurse from the neonatal unit.
Ms Rees said in her statement: "Stephen Brearey was measured throughout... I said that if there were issues, then I needed to know what they were.
"Despite that, he refused to give me any more information. He said that he had evidence, but he refused to show it to me."
Ms Rees said she still does not understand why Dr Brearey would not provide her with more information.
She added: "If they'd have been more vociferous on that Friday afternoon and demanded a meeting with the executive team - with myself as head of nursing, with the divisional director, with the safe guarding team, we would have all got together."
In response Dr Brearey said: "It wasn’t a question of being “vociferous”. We were trying to be objective and professional in a sensitive and difficult situation.
He went onto say: "If she had listened and valued our opinions, further evidence would have come to light sooner."
Granada Reports' Emma Sweeney reports on calls for a public inquiry
It had also been claimed during Letby's trial that Dr Brearey had asked Ms Rees if she would be happy to take responsibility if "something happened to any of the babies tomorrow".
The retired nursing chief is alleged to have said "yes".
But Ms Rees said in her statement that the claim is "completely untrue" and an "outrageous allegation to make".
She added that she is "currently taking legal advice about the untrue allegations".
Ms Rees's statement contradicts the allegations made by Dr Brearey, who told Letby's trial: "She [Ms Rees] was familiar with our concerns already.
"I explained what had happened and I didn't want nurse Letby to come back to work the following day or until this was all investigated properly.
"Karen Rees said 'no' to that and that there was no evidence.
"I put it to her - was she happy to take responsibility for this decision, in view of the fact that myself and my consultant colleagues all wouldn't be happy with nurse Letby going to work the following day?
"She responded she was happy to take that responsibility."
Ms Rees disputes claims she said we would take responsibility for Letby staying on the ward
Cheshire Police say it is are continuing to review the care of some 4,000 babies who were admitted to the Countess of Chester, and also at Liverpool Women's Hospital when Letby had two work placements, during her employment from 2012.
Jane Tomkinson, Acting Chief Executive Officer at the Countess of Chester Hospital NHS Foundation Trust, said: "Following the trial of former neonatal nurse Lucy Letby, the trust welcomes the announcement of an independent inquiry by the Department of Health and Social Care.
"In addition, the trust will be supporting the ongoing investigation by Cheshire Police.
"Due to ongoing legal considerations, it would not be appropriate for the trust to make any further comment at this time."
As Letby becomes the most prolific serial child killer in modern Britain, Gamal Fahnbulleh joins Mel Barham and Emma Sweeney on the latest episode of From the North to look at how she managed to slip under the radar for so long, carrying out her attacks unchallenged for a year.