Ten protestant workmen were murdered in 1976
A man whose palm print was allegedly found on a suspected getaway vehicle used in the Kingsmill massacre will not be prosecuted.
There is "insufficient evidence" to offer a reasonable prospect of convicting the individual arrested on suspicion of murdering 10 protestant workmen in 1976, Northern Ireland's Public Prosecution Service (PPS) said.
The IRA was widely blamed for the massacre, one of the most notorious killings of the Troubles, in which the factory workers were ambushed as they travelled home from work in a minibus in rural south Armagh.
Those on board were asked for their religion, and the only Catholic was told to run away.
The remaining 11 men were lined up outside the vehicle and the killers opened fire. Just one man, Alan Black, survived, despite being shot 18 times.
Michael Agnew, the PPS's assistant director of central casework, said lawyers had "carefully" considered all of the evidence and applied the test for prosecution.
A lack of garda and then-Royal Ulster Constabulary (RUC) records in relation to how the van was forensically handled upon discovery was a key factor in the decision, it is understood.
Prosecutors were apparently unable to find documents indicating exactly when the vehicle was found, where it was taken for examination and the precise location of the palm print position on the windscreen.
This meant that while prosecutors did not see matching the print to the individual to be an issue, the missing forensic records meant they were unable to rule out the possibility his palm might have been placed on the windscreen well after the shooting.
While the PPS did have two witnesses identifying the green Bedford van as being in the general area before and after the attack, the sightings were not close enough to provide circumstantial evidence.
The long-delayed inquest into the murders was put on hold again last year, after it was announced detectives had apparently matched the print to an individual.
Three months later a 59-year-old man was arrested in Newry, Co Down.
The man, who had previous terror convictions, was released pending a police file being sent to prosecutors.
At a subsequent inquest hearing, a lawyer for the Police Service of Northern Ireland (PSNI) said detectives believed the print belonged to the arrested man.
Mr Agnew said: "We are mindful of the disappointment that this decision will bring to the surviving victim and families of those who were killed.
"Although 41 years have passed since this atrocity, we are conscious that their pain endures.
"We have informed the families this morning of our decision and the reasons for it, and have offered to meet with them to answer any further questions that they may have."