Three people who were part of the senior leadership team at the hospital where killer nurse Lucy Letby worked have been arrested on suspicion of gross negligence manslaughter.

Cheshire Constabulary said the suspects, who occupied senior positions at the Countess of Chester Hospital (CoCH) between 2015 and 2016, were arrested on Monday.

All three have since been bailed pending further inquiries, the force added.

Letby, 35, from Hereford, is serving 15 whole-life orders after she was convicted of murdering seven infants and attempting to murder seven others, with two attempts on one of her victims, between June 2015 and June 2016.

Police said corporate manslaughter and gross negligence manslaughter probes are continuing.

Following the arrests, senior investigating officer Detective Superintendent Paul Hughes said: “In October 2023 following the lengthy trial and subsequent conviction of Lucy Letby, Cheshire Constabulary launched an investigation into corporate manslaughter at the Countess of Chester Hospital.

“This focuses on senior leadership and their decision-making to determine whether any criminality has taken place concerning the response to the increased levels of fatalities.

“In March 2025 the scope of the investigation widened to also include gross negligence manslaughter.

“This is a separate offence to corporate manslaughter and focuses on the grossly negligent action or inaction of individuals.

“It is important to note that this does not impact on the convictions of Lucy Letby for multiple offences of murder and attempted murder.

“As part of our ongoing inquiries, on Monday June 30 three individuals who were part of the senior leadership team at the CoCH in 2015-2016 were arrested on suspicion of gross negligence manslaughter.”

A spokeswoman for CoCH reiterated it “would not be appropriate” for the hospital to comment “due to the Thirlwall Inquiry and the ongoing police investigations”.

Police are continuing a review of deaths and non-fatal collapses of babies at the neonatal units of the Countess of Chester and Liverpool Women’s Hospital during Letby’s time as a nurse from 2012 to 2016.

Letby lost two bids last year to challenge her convictions at the Court of Appeal for the seven murders and seven attempted murders, and in October for the attempted murder of a baby girl, which she was convicted of by a different jury at a retrial.

Lady Justice Thirlwall is due to publish the findings from her public inquiry in early 2026.