In many cases that was the last that was ever heard of it; in others some information would later seep out, branding the missing person as an informer or someone who had taken IRA guns or otherwise offended the organisation.
Most vanished at the height of the Troubles, when people were dying at a rate of up to 400 a year, and there was little time or energy for pursuing such mysteries. The killing rate dropped in the 1980s, but it was only after the 1994 IRA ceasefire that the issue surfaced, with unexpected drama and force.
No one who heard it has forgotten the BBC presenter David Dunseith's interview with Helen McKendry, whose mother is among the disappeared. When the Radio Ulster Talkback programme let Mrs McKendry speak for half an hour or so, people everywhere stopped and listened with fascinated horror.
In 1972, Mrs McKendry's mother, Jean McConville, was aged 37. A Protestant, she had moved to the Falls area after marrying a Catholic. He died 10 months before she did, leaving her to bring up 10 children.
Mrs McKendry told how the IRA had taken her mother: "Four girls dragged her from the bathroom at gunpoint. The twins, who were six at the time, were clinging to her, screaming to the women to let her go, but they took her anyway. When the gang left we were terrified. We told no one what had happened because we thought we could survive on our own. Anyway there was always the possibility they'd return for us."
The 10 children tried to survive Christmas 1972 on their own, but when news of the family's situation became known social services moved in and the family was split up. Eight of them were taken into care. One daughter, who was described as mentally disabled, died in 1992.
Mrs McKendry said: "I only spent a year in a children's home, but my brothers and sisters spent nine or ten years in care and their lives have been really damaged by that."
After the broadcast, support flooded in. A campaign was launched. Prominent figures such as President Bill Clinton joined the campaign for the return of the bodies. Other families felt free to speak up, placing the IRA under heavy public and political pressure.
It took more years of campaigning, however, to bring about yesterday's developments. The IRA let it be known that some involved in the killings had died or left the organisation, or were disinclined to give information about murders for which they might yet be prosecuted.
But when it became obvious to the IRA that the issue would not go away, the organisation began a dialogue with the authorities north and south of the border. The outcome waslegislation recently rushed through Westminster and the Dail in Dublin. The Northern Ireland (Location of Victims' Remains) Act received the Royal Assent earlier this week.
This laid down that information given by anyone about the bodies would not be used against them in court. It also placed restrictions on the scientific testing of remains and anything found with them, such as clothing and bullets. The governments specified that this would not prevent post- mortem examinations taking place, and did not amount to an amnesty from prosecution.
These provisions apparently reassured the IRA that it was safe to give up the bodies. Recently the organisation published a list of nine people whose graves had been located, indicating that their bodies would soon be returned.
While the families of the nine hope their long wait is drawing to a close, others have been left in continuing uncertainty. There are more than nine missing people. The families of the others have been left with diminishing hopes of ever being able to give decent burials to their loved ones.
The IRA has admitted the murders of nine people whose bodies are believed to have been buried in secret graves.
The body recovered yesterday is believed to be of Eammon Molloy, from Bone, north Belfast, who vanished in 1975. His brother, Anthony, was killed by loyalists in 1975.
The other eight missing victims are:
Jean McConville, 37, a widowed mother of 10 from Divis Flats, Belfast, who disappeared in March l972.
Kevin McKee and Seamus Wright from Andersonstown, west Belfast, who vanished in October 1972.
Columba McVeigh, 17, from Dungannon, Co Tyrone, who was murdered in l975.
John McClory, 17, and Brian McKinney, 23, who were murdered in March 1978.
Danny McIlhone, from West Belfast, who was murdered in l981.
Brendan Megraw, 24, from Twinbrook, west Belfast, abducted in l975.Reuse content