Police in Britain have arrested three senior officials in the administration of Countess of Chester Hospital who worked there during 2015-2016, on suspicion of negligent manslaughter, following the conviction of nurse Lucy Letby for murdering seven infants in the neonatal intensive care unit. Local authorities reported that the three were released on bail. Nurse Letby was convicted in 2023 of murdering seven infants by injecting them with insulin and air, including a day-old baby, and attempting to murder six additional infants. Following her conviction, the treatment of approximately 4,000 additional infants in the NICU during her employment will also be examined.