A post-mortem examination returned inconclusive results about the cause of death of a new-born baby who was found at a recycling centre.
His body was found at the centre, in Ely Road, Waterbeach on 29 November.
Detective Chief Superintendent John Massey said: “Our investigation into this tragic incident is ongoing and we are still trying to locate the baby’s mother.
“Further medical tests are due to be carried out, but these will take time.
“We are keeping an open mind as to what has happened and are exploring every potential avenue.”
Chief Nursing Officer at NHS Cambridgeshire & Peterborough Carol Anderson said: “We are very concerned for the wellbeing of the mother of the baby boy who was tragically found at a recycling centre in Waterbeach last week.
“We want to put out a direct call to her to come forward for the medical help and support she needs. All NHS doors are open, and our team is ready to help, so please do not be frightened to come forward.
“She can seek help by visiting her local GP, midwifery team or A&E department, or by calling NHS 111 in the first instance if she would prefer.”
The post-mortem examination took place yesterday (Monday)
Anyone with information is urged to pass it to the force online via the Major Incident Public Portal.
If anyone has immediate concerns for someone’s safety, we urge them to call 999.
Earlier Detective Superintendent Massey said: “We would like to make a direct appeal to the baby boy’s mother to contact us – it maybe she needs medical care or is in vulnerable situation.