Patrick ‘Mooch’ Blair was a notorious member of the Provisional IRA before parting ways and becoming involved with a number of armed dissident groups.
The 64-year-old has been linked to atrocities such as the 1998 Omagh bombing which killed 29 people including a woman pregnant with twins.
Blair opposed the peace process and sided with dissidents after the Provisional IRA ceasefires and became an active and senior member of the Real IRA, along with Michael McKevitt.
He was named in the House of Commons as having “helped to construct the Omagh bomb” for the Real IRA.
In 2012, during a hearing of the Smithwick Tribunal investigating allegations that Garda members based in Dundalk colluded with the IRA in the murder of two senior RUC officers, he was named as one of the ambush team.
Chief Superintendent Harry Breen and Superintendent Bob Buchanan were shot dead in south Armagh on March 20, 1989.
An intelligence document read to the tribunal named the notorious republican along with Leonard 'Bap' Hardy as having been involved in the double murder.
Blair later broke the IRA's law of Omerta by giving evidence to the Smithwick Tribunal, admitting he had been actively involved as a "volunteer" in the south Down unit of the Provisional IRA but denying involvement in the Omagh bomb.
In 1975, Blair was sentenced to 15 years for attempted murder of an RUC officer and possession of firearms. He was released from prison in 1982 and moved to Dundalk.
With an address at Lissara Heights, Warrenpoint, Co Down he pleaded guilty in January of belonging to a proscribed organisation, providing weapons and explosives training, conspiring to possess explosives, firearms and ammunition with intent to endanger life.
The charges related to an MI5 sting on members of the Continuity IRA in Newry, that took place on dates between August 11, 2014 and November 11, 2014.
