Tests to identify a human skull discovered in a wooded area could take weeks to be completed.
Forensic experts are examining the skull - believed to be that of an adult male - as search teams comb the private land near Blessington in Co Wicklow.
Over coming days the State Pathologist's office is expected to uncover how long the remains had been in the area, but establishing the identity is expected to take more time.
While gardai have not yet found out who the skull belonged to, the relatives of a number of missing men are understood to have been told of Thursday's discovery.
Among those informed were the family of Paul Byrne, a 20-year-old who disappeared last July.
The father-of-one, whose girlfriend was pregnant with his second child at the time, was last seen in Tallaght, south Dublin after leaving the home of his partner's mother.
Workmen clearing forestry at Ballyfolan near Manor Kilbride made the discovery at around 1.20pm on Thursday.
The scene was sealed off as a specialist Garda dog unit and divisional teams searched the wooded area for more remains.
The skull, which was found on the surface of the ground, is also set to be examined by a forensic anthropologist.
© Press Association