Sunday marks the 24th anniversary of one of the most gruesome atrocities of the Troubles, when the IRA murdered eight Protestant workmen at Teebane.
The bomb, on January 17 1992 in Co Tyrone, destroyed a van carrying 14 civilian Army base workers and left six of them seriously injured.
Innocent Victims United spokesman Kenny Donaldson said: “Twenty-four years on the horror of the Teebane massacre remains a painful daily event for those whose loved ones were murdered.
“IVU along with the families urge members of the nationalist/republican community to search their consciences and come forward with information concerning the identity of those involved.
“Those who hold information and refuse to disclose it are culpable along with the cowards who detonated that deadly bomb.”
Survivor Bobby O’Neill said previously that a “bearded man” walked calmly among the carnage after the bomb. However, he was never asked by police to view photographs of suspects.
Another witness saw a similar man as he passed the spot where the killers laid in wait that morning.
The Historical Enquiries Team (HET) revealed in 2012 that two similar photofits from the men were compiled – of a bearded man – and given to the RUC, but neither were ever published.
HET also found it could not review RUC interview notes due to asbestos contamination.
Nor were the RUC or PSNI able to find any DNA or fingerprint evidence on 19 pieces of evidence from the scene, including sweet wrappers and a cigarette packet.
After the bomb RUC Special Branch officers compiled a list of nine IRA suspects. Five were never arrested but HET could find no reason why.
The roadside memorial to the victims is covered in over 20 marks from violent attacks.