The Ministry of Defence (MoD) must not dodge its responsibility to tell the truth over allegations it was complicit in the Glenanne Gang murders, an MP has said.
Mark Durkan (Foyle) said 120 killings had been connected to the "murderous machinations" of the gang, which is claimed to have involved loyalist paramilitaries working in collusion with members of the Royal Ulster Constabulary (RUC) and the British Army's Ulster Defence Regiment (UDR) in the 1970s.
Referring to research in the recently-published Lethal Allies: British Collusion in Ireland by Anne Cadwallader, Mr Durkan also said the group was able to source a lot of weaponry in arms raids on UDR armouries.
He said documents suggested the MoD knew there were concerns, including the screening of UDR applicants, but did nothing to stem the involvement of Ulster Defence Association (UDA) paramilitary group members in the regiment and the leakage of weapons.
The Social Democratic & Labour Party MP told a Westminster Hall debate: "Many of us tried to scream concerns at the British government, the British establishment, the MoD, and we know there were layers and lines that dismissed and denied that - and denounced those people who offered those concerns as somehow being subversive or irresponsible."
He added: "While there is an important process under way in Northern Ireland that we hope will bring forward ways of addressing some of the wider concerns about the past, that Haass process should not of itself be used by the British Government and in particular the MoD to dodge their responsibility to tell a truth now - a truth that they denied for so very long."
Earlier in the debate, Mr Durkan quoted several documents, including a 1973 report suggesting the ongoing loss of weaponry from UDR armouries and from homes of UDR members.
He said: "A significant report was done in August 1973 called 'Subversion in the UDR' and that report, an MoD report, said, 'Since the beginning of the current campaign the best single source of weapons and the only significant source of modern weapons for Protestant extremist groups has been the UDR.'"
Mr Durkan said it then went on to note significant weapons losses in 1972 and 1973 while the British Government's internal report also indicated between 5% and 15% of UDR soldiers were members of groups such as the UDA, Vanguard Service Corps or Orange Volunteers.
He said: "The report also in another part actually confirmed, 'The discovery of members of paramilitary or extremist organisations in the UDR is not and has not been a major intelligence target'.
"So, here we have just wilful negligence - people recognised there is a risk, they see there has been a pattern of collusion in arms being removed into the clutches of loyalist paramilitaries, they know there's an overlapping membership, but at no point does anybody even make it their business to have this as a serious matter as an intelligence target."
Replying for the Government, Defence Minister Anna Soubry said the allegations were for the police to investigate although the MOD would provide assistance to any investigations that take place should evidence of soldiers committing specific criminal activity emerge.
She told Mr Durkan: "You have raised a very serious issue which I know has been the subject of much comment and debate over a considerable period of time.
"In recent weeks the allegations that members of the security forces were part of a murderous gang which killed more than 100 people in the 1970s have been given further currency in the recently published book to which you have referred to."
Ms Soubry added: "You will be aware that serious allegations such as these are matters which should properly be dealt with by the police and therefore there's very little I can say specifically about them.
"It's right and proper for me to condemn all sectarian attacks by whomsoever they may have been carried out. But I am not able to comment on the accuracy or otherwise of these allegations and it's not for the Ministry of Defence to usurp the function of the police by seeking to carry out investigations about those who may have been involved.
"As I understand it, a number of cases associated with the Glenanne Gang have been investigated by the Historical Enquiries Team but I am not aware those investigations have led to any fresh allegations of specific criminal activity by soldiers that are to be investigated further.
"Of course if such evidence were to be found and produced to the police it would be for them to decide whether any further enquiries should be made. If that was the case my department would provide every assistance to any subsequent investigation."