Former British prime minister Margaret Thatcher was aware of concerns that the North's security forcer were heavily infiltrated by loyalist paramilitaries four years before she became Prime Minister, it was revealed today.
According to files unearthed in the Public Records Office and published in a Belfast newspaper, Mrs Thatcher was alerted of the matter during a September 1975 Downing Street briefing when she was leader of the Opposition.
The meeting involved the then Prime Minister Harold Wilson and the Northern's Secretary of State, Mr Merlyn Rees. It took place two years after a military intelligence document claimed that 50-year-old Lancashire-based sailor Thomas Curry was murdered by loyalists with weapons stolen during a raid on a UDR/Territorial Army base.
According to the memo on the Downing Street briefing published in today's edition of the Irish News, Mrs Thatcher was told it was believed certain elements within the police were very close to the UVF (Ulster Volunteer Force).
The document continued: "The Army's judgment was that the UDR (Ulster Defence Regiment) was heavily infiltrated by extremist Protestants and that in a crisis situation they could not be relied on to be loyal."
During Mrs Thatcher's period as Prime Minister, allegations of security force collusion with loyalists came to a head after the August 1989 Ulster Freedom Fighters murder of 28-year-old father-of-four Loughlin Maginn in Rathfriland, Co Down.
Loyalists showed a reporter pictures of alleged IRA suspects acquired from security sources. Mr Maginn's picture was included in the photo montage and led to the then Deputy Chief Constable of the Cambridgeshire Police Force, John Stevens being sent to Northern Ireland to head up an inquiry into collusion.
Concerns about collusion, however, can be traced back to 1973 in a document entitled 'Subversion in the UDR'. Military intelligence raised concerns in this document a significant proportion of UDR members - between five and 15 per cent - were members of the Ulster Defence Association, UVF, Orange Volunteers or Vanguard Service Corps.
The 14-page paper obtained by the newspaper also raised concerns that members of the regiment had colluded in a series of weapons raids by loyalists on UDR bases in Lurgan, Co Armagh, Belfast and Claudy RUC station in Co Derry.
One of the weapons from the Lurgan raid was later recovered in the loyalist Shankill area of Belfast.
Tests on the weapon revealed it was used in a kidnapping, several attempted murders and most significantly in the killing in May 1973 of Mr Curry, a ship's master from Ashton-in-Ribble, Preston.
Mr Curry, a regular visitor to the North, was gunned down in Muldoon's bar when a hooded UFF gunman opened fire on customers.
The documents have been unearthed in the Public Records Office in London by the Pat Finucane Centre in Derry and Justice for the Forgotten which represents victims of the 1974 Dublin and Monaghan bombings.