The family of a man shot dead by loyalist paramilitaries while undercover troops were at the scene are to push for an inquest into the killing.
A new police report on the attack, where three republicans were ambushed after leaving a police station in Lurgan, Co Armagh in 1990, revealed that eight undercover soldiers were monitoring the men around the time of the killing.
Former republican prisoner Sam Marshall was shot dead but the presence nearby of a red Maestro car, later identified as a military intelligence vehicle, sparked swift claims of a security force role in the killing.
It has now emerged the car was one of six vehicles in a major surveillance operation on the republicans, involving eight armed undercover soldiers, and though the loyalist killers launched the attack and escaped, investigators said there was no evidence of state collusion with the gunmen.
There has never been an inquest into the shooting but the Marshall family's solicitor Padraigin Drinan said she would now be pressing for one to be held, 22 years after the event.
"The family have wanted an inquest all along and on several occasions they have been told there is no need for an inquest because there has been a police investigation into the death," she said.
The attack was claimed by the loyalist Ulster Volunteer Force but the gunmen have never been identified.
A police investigation into a robbery in Belfast led to the arrest of two loyalists later convicted for supplying the killers' car.
A fresh decision on whether an inquest should now be held was delayed until the police Historical Enquiries Team (HET) reviewed the case.
Ms Drinan said the family expects to be in contact with the coroner, adding: "We are now ready for an inquest."
The men targeted in the attack were high-profile republicans including Colin Duffy who was acquitted in January of murdering two soldiers at Massereene army base in Antrim.
But deputy leader of the nationalist SDLP Dolores Kelly said she believed the controversy over the 1990 case subsequently led young people to join republican paramilitary ranks.
She said: "I am convinced that this murder led other people to take up the gun during the last ugly years of the Troubles. The HET owe Sam Marshall's family and the wider public the truth."
Sinn Fein's John O'Dowd said: "How men armed with rifles were able to drive through an area which had such a heavy presence of British intelligence operatives, park their car, get out, open fire with a barrage of shots and then return to the vehicle and leave the area has to be explained."
The three republicans had been signing in at Lurgan police station as part of bail conditions for charges of possession of ammunition.
The HET praised much of the original RUC investigation and found no new lines of inquiry. It said its review found no evidence of collusion.
But the Marshall family complained that the HET did not re-interview the soldiers but only relied on RUC statements from the time.
The HET found:
- A military commander at a remote location monitored a unit of eight undercover soldiers, including two with camera equipment at the entrance of the police station
- The armed military intelligence personnel at the scene were in six cars, including the noted red Maestro;
- Two other undercover soldiers followed the republicans on foot and were within 50-100 yards of the attack but said they did not to see the killing in which the gunmen fired 49 shots
- After two masked loyalists jumped from a car and started shooting, the troops did not return fire, claiming it was out of their line of sight and too far away, but alerted colleagues who launched an unsuccessful search for the killers - and despite being in a republican area, the soldiers make no reference to feeling at risk from the gunmen
- The killers' guns are believed to have been used in four other murders and an attempted murder. Similar weapons are linked to seven further killings and four attempted murders in 1988-89
- The RUC found gloves near the gang's burned-out getaway car, but the gloves were subsequently lost
- The RUC sought to deny the existence of a surveillance operation by giving "misleading or incomplete" statements. But RUC Special Branch had briefed the undercover troops
- Investigators could not rule in or rule out that the RUC had leaked information to the loyalists. But they said the killers may have gathered their own intelligence
Murder weapons 'smuggled into Northern Ireland by agent'
The guns used to kill Sam Marshall were from a haul smuggled into Northern Ireland by a top security force agent, the murdered man's family has claimed.
Brian Nelson was a leading member of the loyalist Ulster Defence Association (UDA) and a prized asset of military intelligence.
But he has been linked to a string of controversial killings, including the murder of Belfast solicitor Pat Finucane in 1989.
The HET (Historical Enquiries Team) was unable to answer all the questions posed by relatives over the weapons used in the Sam Marshall murder.
But the family obtained a copy of the original RUC (Royal Ulster Constabulary) report on the killing, after the document was handed to a US court as part of an extradition case in 1993.
- It confirmed the guns were VZ58 automatic rifles, similar in appearance to the infamous AK47 weapon.
- Victims groups have said the rifle model was among a consignment smuggled into Northern Ireland for use by loyalist paramilitaries in the late 1980s with the help of Brian Nelson.
- The rifles formed part of a major arms shipment from South Africa and the entire stockpile has been linked to 95 of the estimated 225 loyalist murders carried out in the six years following the arrival of the cache.
The family further claimed that by comparing information with other victims of loyalist violence, they have directly linked the guns that killed Sam Marshall to four other murders and an attempted murder.
The Marshall family has also questioned whether the description of a man seen acting suspiciously near Lurgan police station on a previous bail signing by the three republicans matched that of Robin Jackson.
The leading UVF member, known as "The Jackal", featured in a recent HET report on the murder of members of the Miami Showband pop group in 1975, which pointed to collusion by security forces.
The HET said attempts by the RUC failed to link the description of the man seen in Lurgan to known loyalists.
Rosemary Nelson, a Lurgan solicitor who took up the Marshall family's case, was killed by loyalists in 1999 amid allegations of state collusion.
An inquiry said the state was not directly linked to her killing, but it could not rule out involvement by rogue security force members and it was heavily critical of the RUC and government.
It concluded Mrs Nelson's life was threatened by RUC officers, that police assaulted her in public, and leaked intelligence - all of which contributed to making her a target.