Lucy Letby was not referred to the nursing regulator after concerns about her were raised to hospital bosses because there was a "lack of evidence" she may be killing babies, a public inquiry has heard.
Doctors on the neonatal unit at the Countess of Chester Hospital had raised their concerns in June 2016 after the deaths of two triplet boys.
The Thirlwall Inquiry heard the director of nursing had phoned a Nursing and Midwifery Council (NMC) employer link representative, Tony Newman, on 6 July 2016.
Mr Newman told the hearing that Alison Kelly had told him there was a rise in mortality of babies but she did not say a nurse was suspected of deliberately harming babies.