The search for one of the IRA's so-called Disappeared victims has resumed in a vast bog in Co Monaghan.
Columba McVeigh was 17 when he was abducted and murdered by the IRA in Dublin in October 1975.
The painstaking search began again yesterday near Bragan in Co Monaghan by the Independent Commission for the Location of Victims' Remains (ICLVR).
The site in the Republic was excavated last April and again in the autumn, when the search was halted due to extreme weather conditions.
The commission said yesterday's search marked the restart of the previous search operation.
"Regrettably, to date, the remains of Columba McVeigh have not been found," it said.
The missing teenager was from Donaghmore in Tyrone, but vanished while living in Dublin.
Columba's relatives have had their hopes raised several times over the last few years when a series of digs was ordered in the county to end their near-38-year search for answers over his killing and disappearance. His mother Vera died six years ago, before his body could be found.
Despite extensive searches across Monaghan he remains on the list of the Disappeared.
Hundreds of mature trees on the bog near Bragan were cut down last year to open the site up for excavation, and to also allow forensic archaeologists to inspect roots.
Fifteen men and one woman were murdered and secretly buried by republican paramilitaries during the Troubles.
More than 52 acres of land has been excavated by the commission, which was set up after the Good Friday Agreement, in the ongoing search for all of the Disappeared.
The remains of Columba, Joseph Lynskey, Seamus Wright, Kevin McKee, Robert Nairac, Brendan Megraw and Seamus Ruddy have all yet to be located.
The commission made a fresh appeal for anyone with information to come forward.
"Any information received is entirely confidential and can only be used to locate victims," the commission said.