Dissident republican Tommy Crossan was shot dead in Belfast yesterday, police have confirmed, saying he was shot several times while he sat in an office.
A 26-year-old man was arrested by the Police Service of Northern Ireland today in connection with the killing of the 43-year-old father-of-six, who was a former senior member of the Continuity IRA (CIRA).
Crossan, who also had five grandchildren, was gunned down at a fuel depot in the grounds of an industrial complex in full view of surrounding houses yesterday afternoon.
Senior investigating officer detective superintendent Jonathan Roberts said: "At around 4.45pm Mr Crossan was shot a number of times at close range in his upper body area as he sat in the office of the business of a family friend within the Peter Pan complex."
He added: "The murder of Mr Crossan on the Springfield Road yesterday was a brutal and ruthless attack which has no place in society.
"Mr Crossan was known to police but no matter what his lifestyle was, absolutely nothing justifies this barbaric action against him.
"Police are working on a number of lines of inquiry. One line of inquiry centres on individuals or groups who would associate themselves with dissident groupings, however we are keeping an open mind."
Mr Roberts said police also wanted information about a red BMW, registration OEZ 9177, which is believed to be linked to the murder. It was found burned out a short time later in the Beechmount Grove area of Belfast, he said.
The man arrested over the killing was being questioned today at the serious crime suite in Antrim.
A priest attended the scene to pray over Crossan after he was shot in West Belfast, an area long known as a republican heartland but which has been relatively peaceful in recent years following the end of the IRA campaign in 1998.
Relatives gathered in tears at the scene, their devastation visible to onlookers.
Crossan was once the CIRA's Belfast leader but was believed to be the subject of a death threat and had been expelled from the group some years ago after a fall out.
He served time in prison for conspiracy to murder Royal Ulster Constabulary (RUC) officers following a gun attack on a police station in West Belfast in 1998.
The CIRA has opposed the peace process which largely ended three decades of violence and transformed Northern Ireland. Crossan was killed on the 16th anniversary of the Good Friday Agreement which mandated political power-sharing at Stormont.
Political figures from all sides of Northern Ireland's political landscape have condemned the killing, including First Minister Peter Robinson and Deputy First Minister Martin McGuinness.
Mr Robinson said: "The small minority of people who want to continue terrorising the community need to understand that they will not be allowed to drag Northern Ireland back to the dark days of the past. They must be hunted down and brought to justice."
Mr McGuinness added: "The people behind this killing are criminals and will further no cause through this shooting. Whoever carried out this act has nothing to offer the community and have no role to play in our future.
"Dialogue not destruction is the way forward and while there may be a small minority of people who are trying to promote division and heighten tensions, let's be very clear, they will fail.
"The peace process is rock solid and all right-thinking people across the community oppose and reject the actions of the people behind this murder."
Belfast's Lord Mayor, Mairtin O Muilleoir of Sinn Fein, said the killers existed in the dark margins of society but could not slow the pace of change in Belfast.