Top medical experts have been called in to investigate the sudden deaths of four infants at a hospital in Derry.
Coroner John Leckey today confirmed the appointments after launching an investigation after the four died over a period of weeks at Altnagelvin Hospital.
A statement by his office said: "The investigations are complex and will take some time to complete."
The experts are Professor William Thompson, Emeritus Professor of Obstetrics and Gynaecology at Queen's University Belfast, Professor Sabaratnum Arulkumaran of the Department of Obstetrics and Gynaecology at St George's Hospital Medical Schools, London, Dr John Jenkins, Senior Lecturer in Child Health at Queen's, and consultant paediatrician at Antrim area hospital.
Details of the sex and ages of the four infants who died have not been disclosed, but the inquiry has been running since September.
The statement by Mr Leckey, senior coroner in Northern Ireland, added: "Once the reports have been received from the experts, the need for inquests will be considered by the Coroner."
Post mortem examinations will have been carried out as part of the inquiry, and even though the families will be kept informed throughout the process, it's not clear how long the investigation will last.
A spokesman for the hospital said today: "Any unexpected death is always a source of sadness for our staff and we have given our sincere condolences to the bereaved parents and families.
"We are co-operating fully with the coroner's investigations and we believe it is inappropriate for us to make any further media statements on this matter pending the completion of the investigation."
Derry city SDLP Councillor Seana Hume, who is also a member of the Western Health and Social Services Council, said it was right and proper the hospital should refer these cases for an investigation.
She added: "I hope the inquiry will be open and transparent at all stages. This will be an incredibly difficult time for the families of the deceased infants and to avoid any more unnecessary suffering I hope the inquiry is processed as quick as possible.
"But the inquiry needs to be thorough and the families need answers."