Investigators searching for the remains of 'disappeared' Columba McVeigh have said their determination to find him is "undiminished".
A search that began in the Bragan Bog in Co Monaghan in August is continuing, as investigators prepare to move their focus to a new section of the bog.
The update comes ahead of the 50th anniversary since Columba McVeigh was abducted, murdered and secretly buried by the IRA in October 1975.
He is one of the "Disappeared" victims of the Troubles whose bodies have still to be found.
The lead investigator with the Independent Commission for the Location of Victims' Remains (ICLVR) said a search that started in August is continuing.
Eamon Henry said that it is now moving to a section of Bragan Bog that is roughly eight acres in size.
"Active searching was paused briefly because of deteriorating ground conditions in spells of bad weather and we took that opportunity to undertake the necessary restoration work on the disturbed areas of the bog to preserve its ecological integrity," he said.
Mr Henry said that as the 50th anniversary approaches, "the pain and anguish this causes his family is almost impossible to imagine".
"We are doing everything in our power to recover Columba's remains and while it is frustrating for us and deeply disappointing for the McVeigh family that we have not yet found him, our determination to do so is undiminished. If he is here we will find him."
Mr Henry appealed for anyone with information on any of the four outstanding ICLVR 'Disappeared' cases - Joe Lynskey, Columba McVeigh, Robert Nairac and Seamus Maguire, to contact them and said that all information is treated in the strictest confidence.
