Among republican and security sources there was always little doubt that the Markethill bomb was the work of the Continuity IRA. Until the explosion which devastated the Co Armagh town a week ago, CIRA had been little more than a minor irritant to the security forces and the mainstream republican movement.
Last year, it bombed the Killyhevlin Hotel in Fermanagh, a commercial target. But all its other attacks over the past two years have failed.
The Markethill bomb, aimed at the local RUC station, was the group's first "successful" military target.
The location does not appear to have been chosen because CIRA wanted to provoke dissident loyalists opposed to the peace process living in the Armagh/Craigavon area, although concern is indeed growing that the Loyalist Volunteer Force might retaliate.
Markethill was probably targeted because its proximity to the Border ensured a safe getaway for the bombers and because the RUC base had been bombed many times before by the Provisional IRA and the CIRA is eager to establish a continuity with the past.
CIRA has its roots in the Sinn Fein split on abstentionism in 1986. It was formed by disillusioned IRA members who supported the breakaway Republican Sinn Fein group of Mr Ruairi O Bradaigh and believed that Mr Gerry Adams and Mr Martin McGuinness were abandoning traditional republican principles.
However, it wasn't until the Provisional IRA's 1994 ceasefire that CIRA started expanding. It is understood that it now has about 100 members. Some, but by no means a majority, would be experienced operators.
Disillusionment with the peace process in hardline republican areas has aided CIRA's recruitment. It is attracting disaffected Provisionals in Border areas, particularly in south Armagh, and it is the largest republican paramilitary organisation in Fermanagh.
It has units in Belfast, and graffiti supporting CIRA have gone up in Andersonstown in recent days. However, deep loyalty to the Provisional leadership and its tight hierarchical structure have meant that CIRA has made fewer inroads in Belfast than elsewhere.
CIRA suffered a grave setback in the city when its leader, an experienced activist who had previously been responsible for several high-profile killings for the IRA and INLA, was arrested. But despite some successes, the security forces on both sides of the Border have so far failed to penetrate CIRA.
The problem for Provisional leaders is that the more attacks CIRA carries out, the more likely some disaffected Provisional members are to defect. Such recruits would have considerable hands-on experience and would have the potential to take CIRA's campaign on to a more aggressive level.
CIRA has access to commercial explosives, although it is unknown if it possesses Semtex. It is believed to have recently procured arms from the US where it has some support among militant Irish-Americans.
The group aims to escalate its campaign as the peace process progresses. Its main targets, sources say, will be RUC officers, British soldiers, and military bases.
Although it is unknown whether the organisation has the capability, it has threatened to bomb Britain. It believes that the Provisionals' pre-1994 bombing campaign in England was "very successful".
It has, however, no plans to launch an offensive in the North against loyalist paramilitaries or their political representatives.
"That would only give legitimacy to the British claim that the conflict is between two warring tribes," a CIRA leader said.
So far CIRA has not carried out any gun attacks in the North and it is believed that it will continue to concentrate on developing large home-made bombs in the immediate future.
The group is still incapable of mounting a sustained campaign but security sources do not underestimate its threat.
"We probably didn't take them [CIRA] seriously at first," said a source. "They were very quiet for a long time but they seem to have been putting things in place during that period.
"They didn't play to the media by launching hasty, ill-conceived attacks and we were perhaps too busy concentrating on what the Provos were up to. I think that will change now."
Security sources fear that in the event of an IRA split, CIRA's ranks would be swollen by dissidents.
In 1985, the Provisional leadership expelled several of its own leading militants in Belfast and threatened them with death if they attempted to set up a rival organisation.
There is no doubt that the Provisional hierarchy would like to wipe out CIRA. But taking military action against the group could cause further dissension in republican areas where there is already disquiet about the peace process.
Ironically, Provisional leaders could well find themselves relying on the security forces to deal with the threat of militant, unyielding republicanism.