A senior Sinn Fein leader has admitted the IRA perpetrated "massive injustice" on the victims it abducted, murdered and secretly buried during the Troubles.
Pat Doherty, MP and MLA for West Tyrone, urged ex-paramilitaries to give up any information about the whereabouts of makeshift graves for the remaining so-called Disappeared.
The former Sinn Fein vice-president said: "There has been a massive injustice committed by republican forces in the north during the conflict. The benefit that can be done to resolve it, needs to be done."
The call swiftly followed a warning by the Independent Commission for the Location of Victims' Remains that it has now run out of clues in its search for seven bodies yet to be found.
Around 52 acres of mostly bleak, barren and remote bogland has been excavated so far by the commission, set up after the Good Friday Agreement.
Nine bodies have so far been recovered but the remains of Joseph Lynskey, Seamus Wright, Kevin McKee, Columba McVeigh, Robert Nairac, Brendan Megraw and Seamus Ruddy have yet to be located.
However, Geoff Knupfer, the investigative scientist leading the search, acknowledged "enormous support" from the IRA.
Mr Knupfer, who helped find the bodies of the victims of Moors murderers Ian Brady and Myra Hindley, said several people were involved in every disappearance investigated.
The Irish Government alone has spent four million euro (£3.3 million) over the past six years on searches.
Sinn Fein's Sean Crowe told a parliamentary committee in Dublin that he is uncomfortable with the commission's presentation which he said does not fully reflect the horror and terror victims went through, and the heartbreak of their families.