A former Army captain says he is prepared to tell an official inquiry how attempts to expose child abuse at the Kincora Boys' Home were blocked by MI5.
Colin Wallace, a psychological warfare expert who served in the Army during the Troubles, says he and a number of other retired officers would be prepared to give evidence.
It follows calls for the east Belfast home to be included in a Government inquiry into child sex abuse. In 1981 three senior care staff at the home were jailed for abusing 11 boys.
Mr Wallace feels the inquiry could be the last chance to find out the truth of what happened at Kincora.
He said: "David Cameron has said no stone will be left unturned in uncovering child abuse rings in the 1970s and 1980s.
"Well, I can tell him there was a lot of information on Kincora, but people who know about it are dying and files may be destroyed. This is the last big opportunity to put Kincora and the other children's home allegations to rest for good."
Mr Wallace stated: "When I was working with military intelligence the Army did want to expose Kincora but MI5 didn't. That led me to the conclusion that MI5 had some extra interest.
"Some in the RUC also tried to uncover it but were stymied. Whoever was stopping further activity had a lot of influence."
Wallace (71) is now a management consultant. He worked in the British Army's Information Policy Unit in Northern Ireland between December 1971 and September 1974.
During that time he tried to make official knowledge of the Kincora scandal public with the support of more senior Army officers.
Since leaving the Army he said he had been told that boys from Kincora were being taken to Brighton to be abused.
While in the Army he believed well-connected paedophiles were using the home, including Sir Knox Cunningham, who was parliamentary private secretary to former PM Harold Macmillan.
The abuse allegations in the home centred around a secretive loyalist paramilitary organisations known as Tara, which met in Clifton Street Orange hall at the time and was largely made up of Orange Order members. Some, like William McGrath, who was later jailed for child abuse at Kincora, were in an Orange lodge known as Ireland's Heritage.
Mr Wallace said: "We in the Army were looking at Tara as a paramilitary organisation on the fringe of the conflict from 1970 on. The emphasis changed late in 1972 when we got a call from a woman who was either a welfare officer or probation officer, and I was delegated to meet her."
The woman told him that she was dealing with a Kincora resident who had been in trouble with the police.
The boy had told RUC officers that sexual assaults were taking place at the home and, although they were sympathetic, the officers told her that they were being blocked at a higher level from doing anything.
In 1973 Capt Wallace prepared a briefing paper for journalists which set out allegations about Tara and its role in homosexual activity in Kincora and named Sir Knox. It was mentioned in a number of papers but no action was taken. "We didn't specify allegations of assault in the home because the Army felt that it couldn't be seen to be briefing on a police matter. However, we gave the names of those involved," he said.
In 1974 Wallace and his colleagues received documents from the RUC showing that although some officers were aware that McGrath was a child abuser, they were obstructed from pursuing him. Wallace also tried to make this public.
After that he was removed from his job, accused of passing a classified document to a journalist, and eventually charged and convicted of murder. Years later it emerged that he had been cleared to pass the document and the murder conviction was quashed.
Asked if he believed it was an attempt to discredit his allegations Mr Wallace said: "I can't prove that, but when I asked a former colleague why he didn't speak out he told me: 'Look what happened to you'."
He added: "The terms of the inquiry would need to be watertight if people are to have the confidence to co-operate with it fully."
Kincora was a boys home which operate in east Belfast between 1960 and 1980. In 1980 Lord Fitt and the Irish Independent revealed a child abuse ring operating in the home. In 1981 three senior care staff at the home were jailed for abusing 11 boys but allegations of a wider ring with links in the political establishment have persisted. There are calls for Kincora to be included in a British Government probe into high-level child abuse in Britain.
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