Unidentified Gardai colluded with the IRA in the murder of two RUC officers in 1989, The Smithwick Tribunal has found.
Judge Peter Smithwick said it was probable that a mole within Dundalk Garda Station told the IRA that the two RUC officers were at a meeting in the station before they were ambushed in South Armagh.
Superintendents Harry Breen and Bob Buchanan were two of the most senior members of the RUC to be murdered during the Troubles
The Justice Minister Alan Shatter has apologised unreservedly for any shortcomings on the part of the State identified in the report.
The Garda Commissioner Martin Callinan has welcomed the publication of the report of the Swithwick Tribunal - but says he will need time to carefully examine its findings and recommendations.
The inquiry report, which took over 8 years to complete, extends to several hundred pages.
Bob Buchanan's son William was there for every day evidence was heard.