THE families of two men murdered by loyalists have called on police to say why a known UDA commander has never been questioned about the killings.
An investigation by the Historical Enquiries Team (HET) has found that security force collusion was likely in one of the attacks, which were just eight days apart.
Father-of-eight Jim Loughrey was shot at his home at Greysteel, Co Derry, on November 14 1976.
John Toland, a father-of-seven from Derry city, was targeted while working as a barman at nearby Eglinton on November 22.
Mr Loughrey died three days after Mr Toland was shot.
Derry UDR member David Hamilton admitted taking part in Mr Toland's murder but was acquitted at trial after arguing his admission was made under duress.
He was convicted of possessing a gun used in the attack and sentenced to five years' imprisonment.
The HET said: "It is likely there was collusion between individual members of the security forces and those responsible for John's murder."
The enquiry team said that while no evidence of security force collusion was found in Mr Loughrey's murder, it could not be ruled out.
The families of both murder victims yesterday said the HET reports threw up unanswered questions, particularly about the role of a leading loyalist.
John Toland's son Danny said there was evidence that his father's murder was planned and ordered by a known UDA 'brigadier' in Derry.
He said the UDA leader intended taking over the bar where his father worked after the murder.
"This man, a former B Special according to the HET, also ordered the murder of John Loughrey," he said.
Mr Toland said despite being placed on the police national computer in the 1980s and his whereabouts being known, the loyalist was never questioned.
John Loughrey said that the same guns, the same UDR source and the same organisation involved in Mr Toland's murder were involved in his father's death.
He criticised the HET's conclusion that collusion merely could not be ruled out.
At a press conference at Derry's Pat Finucane Centre, both Mr Loughrey and Mr Toland spoke of the impact of the murders on their respective families.
The families also called on Chief Constable Matt Baggott, the Director of Public Prosecutions Barra McGrory and secretary of state Theresa Villiers to investigate why the role of the known UDA leader was never addressed.
They suggested that he may have been acting under orders from security agency handlers.
Mr Loughrey said: "Could murders, including those of my father and John Toland, have been prevented?" ■ IMPACT: John and Pauline Loughrey whose father was murdered by loyalists in 1976. Right, Danny Toland and his mother Marie whose husband John was also murdered