The remains of an infant found in Co Cork are at least 20 years old and possibly older.
Gardaí are following a definite line of inquiry following the discovery last weekend.
Officers received specific information, which led to a search just outside Killeagh.
Ralph Riegel is southern correspondent with the Irish Independent.
He told Newstalk Breakfast: "It's believed the remains are at least 20 years old, possibly longer.
"The full remains were recovered, they were taken to the morgue near Cork University Hospital.
"A full post-mortem examination has been conducted.
"Gardaí have also requested the assistance of a forensic anthropologist - what they've said officially is that the results of those two examinations will determine the nature of their investigation.
"But given the sensitivity with which this is being dealt with, I think really what could lurk behind all of this is a personal tragedy".
He said it is believed they know who the mother is.
"The indications that I got from my Garda sources last night was that they do believe they know the identity of the child that they're dealing with in terms of the mother and the family.
"But how they progress from here will be determined by the results of those two tests".