Mr O'Callaghan shot and killed a Special Branch detective in Omagh in 1974 and was linked to a fatal mortar attack the same year
The double agent was alleged in 2003 to be Freddie Scappaticci, a claim he has consistently denied
Northern Ireland Secretary Theresa Villiers called on paramilitary organisations in the region to disband
Irish president Michael D Higgins and Garda commissioner Noirin O'Sullivan lead tributes
Deputy First Minister says killings had not been in the interest of Sinn Fein
The sister of one IRA victim said Corbyn's refusal amounted to an “insult to all our dead loved ones"
This veteran intellectual giant of the frothing right has been a delight since first being elected in 1983
Nationalist leader had blamed unionists for former US diplomat Dr Richard Haass’s failure
Gene Hetherington finally collects her BA in Commerce at a ceremony alongside her 23-year-old granddaughter
The Tories don’t have a great record on acknowledging his contribution to peace in South Africa
Superintendents were betrayed by Garda counterparts after visit south of border, inquiry concludes
Tributes paid to Father Alec Reid, trusted go-between of both the IRA and British Government
Former IRA commander repeatedly abused Aine Adams when she was aged between 5 and 9
David McKittrick reports on former terrorist’s visit to Warrington, where two boys died 20 years ago in bombing
Northern Ireland deputy first minister Martin McGuinness has criticised the British government’s decision not to set up a public inquiry into the Omagh bomb attack which killed 29 people in 1998.
Arbitrary government decisions have been highlighted by both the left and right