A coroner has urged suspects linked to the murder of 10 Protestant workmen by the IRA more than 40 years ago to come forward.
In a highly unusual step, Brian Sherrard issued a public appeal for information about the Kingsmills massacre.
He specifically referred to people arrested at the time or who were under suspicion.
The 10 victims, who were textile factory workers, were shot dead when gunmen ambushed their minibus in January 1976.
A fresh inquest into the murders was ordered in 2013 by Attorney General John Larkin.
It is scheduled to open on May 23 in Belfast.
The sole survivor of the massacre said yesterday he hoped those involved in the killings will come forward before the case begins.
Alan Black said: "It has gone past the point of calling for anyone to be punished. This is about getting to the truth.
"It has been like a raw wound for 40 years and this is about bringing some form of comfort to the families."
Mr Black, now 72, added: "The gunmen were probably around the same age as myself, so we are now looking at our own mortality.
"You would want to ease your own conscience before passing on."
The Coroners Service issued an appeal for information yesterday ahead of the inquest.
A statement said: "The coroner, His Honour Judge Sherrard, requests that if anyone can assist this inquest in examining these deaths, they should make contact with the Coroners Service.
"There may, for example, be persons with relevant information concerning the deaths but who have not yet brought that information to the attention of the authorities.
"There may be persons who were arrested in connection with the deaths and who wish formally to renounce any connection with the matter.
"Or there may be persons who have been mentioned in connection with these deaths or who have regarded themselves as under suspicion in relation to the deaths, who wish formally to renounce any suggestion of their involvement or who have information that may assist the coronial inquiry."
This year marked the 40th anniversary of the massacre.
The men were murdered as they travelled home from work together along the Whitecross to Bessbrook road in rural south Armagh.
As their minibus cleared the rise of a hill, there was a man standing in the road flashing a torch. The van stopped and 11 other men, all of them armed, emerged from hedges around the road.
After checking their religion, the gang ordered one Catholic worker, Richard Hughes, to leave.
The gunmen then opened fire.
The 10 who died were John Bryans, Robert Chambers, Reginald Chapman, Walter Chapman, Robert Freeburn, Joseph Lemmon, John McConville, James McWhirter, Robert Samuel Walker and Kenneth Worton.
Mr Black survived the bloodshed, despite being shot 18 times and left for dead.
The IRA never admitted involvement and was supposed to be on ceasefire at the time.
The name South Armagh Republican Action Force was used to claim the murders.
No one has ever been convicted.
The original inquest in 1978 lasted just 30 minutes and recorded an open verdict.
In June 2011, an investigation by the Historical Enquiries Team found that the IRA was responsible for the attack and that the victims were targeted because of their religion.
Anyone with information in relation to the deaths can write to the Coroners Service before May 23, or email firstname.lastname@example.org