During the Troubles, at least 13 people were disappeared by republican paramilitaries. Of these, 12 were abducted and secretly buried by the IRA. Only one, Newry schoolteacher Séamus Ruddy, was the work of the INLA.

In 1999, the IRA issued a statement admitting nine disappearances. Missing from the list were Crossmaglen men Gerard Evans and Charlie Armstrong, and British Army captain Robert Nairac, 29. He was omitted because, as a military figure, he was considered a legitimate target. He disappeared in 1977 after drinking in a south Armagh pub.

Since the IRA's admission, five bodies have been found. The first was that of Eamon Molloy, 25. His body was left in a coffin under a tree in a graveyard near Dundalk in 1999. An IRA man from Belfast, he disappeared in 1975 and was killed for allegedly being an informer.

The remains of John McClory, 17, and Brian McKinney, 22, were discovered next in 1999. They were in a double grave near Iniskeen, Co Monaghan. They were killed in 1978 for allegedly stealing an IRA gun to use in a robbery. Two million gallons of water was pumped out of Colgagh bogland during the search.

The body of Jean McConville, 38, a widowed mother of ten, was discovered on Shelling Hill beach, Co Louth, in 2003. She had been abducted from Divis Flats in west Belfast in 1972. The IRA said she was an informer. Her family denied this, claiming she was killed because she had helped a dying British soldier.

The last body to be recovered was that of Danny McIlhone, 19, from west Belfast. The IRA said he was killed for stealing guns and wasn't suspected of being an informer. Other sources dispute this. His remains were found last November in the Wicklow Mountains.

Those still missing include Séamus Wright, 25, and Kevin McKee, 25, from west Belfast. They were the first people to be disappeared, in 1972. Republican sources say they were informers.

Searches in Co Monaghan for Columba McVeigh, 17, from Donaghmore, Co Tyrone, have so far yielded nothing. The IRA claim he was killed because he was an informer, which his family strongly deny.

The body of Brendan Megraw, 22, from west Belfast hasn't been found despite searches near Navan. A masked gang injected his wife with a syringe, then waited for him to return home to abduct him. He was allegedly a British agent.

A two-day search in Co Monaghan for Gerard Evans, 24, ended unsuccessfully last week. Searches in Co Monaghan for Charlie Armstrong, 57, who disappeared driving to Mass in 1981, have so far failed. But the Sunday Tribune has been told he is buried near where digging has taken place.

The INLA has admitted killing ex-member Séamus Ruddy, 33, who disappeared in Paris. It says he is buried in a forest near Rouen but his body hasn't been found. No reason has publicly been given for his murder.