A manager at the hospital where Lucy Letby worked has been arrested on suspicion of perverting the course of justice in connection with an investigation into the child killer.
They were detained as part of the probe into corporate manslaughter and gross negligence manslaughter at the Countess of Chester Hospital, Cheshire Constabulary said.
Officers carried out a search warrant at a property on Wednesday and the individual was arrested and later bailed pending further inquiries. Their name has not been made public.
"Both the corporate manslaughter and gross negligence manslaughter elements of the investigation are continuing and there are no set timescales for these," the force said.
The force previously arrested three individuals who were part of the senior leadership team at the hospital between 2015 and 2016 on suspicion of gross negligence manslaughter. They were bailed pending further enquiries.
The individual arrested on Wednesday is one of those three people.
Letby, 35, is serving multiple whole-life sentences for murdering seven children and attempting to murder seven more between June 2015 and June 2016 while working in the hospital's neonatal unit.
Earlier this year, inquests into the deaths of five babies murdered by Letby were opened and adjourned.
Senior coroner for Cheshire Jacqueline Devonish said that she was satisfied each child needed an inquest, and provisionally scheduled the hearings for September, dependent on the outcome of the public inquiry into how Letby was able to commit the murders.
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It came after prosecutors decided in January that she wouldn't face further charges after police submitted evidence related to nine other children, two of whom died.
The Crown Prosecution Service said the evidential test had not been met in any of the cases.
Letby, from Hereford, has twice been denied permission to appeal against her 2024 convictions.
However, the Criminal Cases Review Commission, which investigates potential miscarriages of justice, is considering evidence submitted on her behalf by medical experts that suggests poor care and natural causes were to blame for the deaths.
(c) Sky News 2026: Manager at Lucy Letby hospital arrested on suspicion of perverting course of justice
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