Although they are, on paper, separate organisations, the two dissident republican groups appear to have buried their differences in the interests of mounting a combined terrorist campaign in Northern Ireland. Both are vehemently opposed to the Belfast Agreement and both have tried to smash it through acts of violence.
The "Real IRA", which was responsible for the Omagh bomb atrocity in August 1998 in which 29 civilians were killed, is the larger of the two, with dozens of members in the north Louth and south Armagh area. After Omagh it retreated into its strongholds for almost a year before re-starting its campaign.
Since the start of this year it has mounted about a dozen attacks in Northern Ireland - mainly mortar, bomb and rocket attacks. None of these has caused death or serious injury but there is growing concern among security forces on both sides of the Border that the "Real IRA" is becoming a significant threat.
The dissident group has already attempted two mortar attacks on military bases, at Roslea in Fermanagh and in south Armagh. It has also attempted to fire a Russian-manufactured rocket at a police barracks in Co Tyrone and has planted two bombs, both of which failed to explode, at army bases in Derry.
It also planted a bomb, which also failed to explode, at the Secretary of State's residence at Hillsborough, Co Down. The group managed to establish a unit in London, which was responsible for planting a small bomb in Ealing Broadway two weeks ago and another under Hammersmith Bridge in May. Forensic tests on the remains of the Hammersmith Bridge bomb confirmed it was identical in manufacture to a device found by gardai in a search of a house in Ballyfermot, Dublin, on May 25th.
The "Real IRA" was created in the autumn of 1997 when a group of dissidents walked out of a Provisional IRA leadership meeting in Donegal, called to discuss acceptance of the terms of the Belfast Agreement, including the prospect of decommissioning weapons.
The exact extent of support for the "Real IRA" is not known but sources in the Border area report that it is growing. It is also reported that a meeting of Provisional IRA members was called in June and warnings issued by local leaders that defections to the "Real IRA" would lead to retaliation.
According to security sources in the North, it appears the "Real IRA" is improving its operational ability and it is only a matter of time before one of its devices explodes at or in a security installation in the North. The Garda believes there has been collusion between the "Real IRA" and the other splinter republican terrorist organisation, the Continuity IRA, at leadership level for the past year.
The Continuity IRA first emerged in 1991. It is associated with the splinter political group, Republican Sinn Fein, one of whose founder members remains in prison on explosives charges relating to a Continuity IRA bomb.
While both groups remain separate it appears they may be feeding off each other's strengths. The Continuity IRA appears to have established links over a year ago with former Yugoslavian arms dealers in Croatia. Some time last autumn a quantity of RPG18 anti-tank rockets, plastic explosive, electric detonators and a small number of guns were smuggled into the State. The source was said to be in Croatia.
It now seems that while the Continuity IRA members set up the arms contacts, the "Real IRA" raised the money for the shipment through cigarette and other contraband smuggling.
A senior "Real IRA" figure who lives on the Border, north of Dundalk, is in charge of the organisation's cigarette-smuggling wing.
Since the beginning of this year, both groups seem to be involved in joint arms acquisition and a combined campaign of attacking security force targets in the North, as well as the disruptive bombing campaign in London.
It is believed the Continuity IRA attacks are based mainly in the west, as it has members in the north Cavan and Fermanagh area. Its members are believed to be responsible for two bomb attacks - in Irvinestown, Co Fermanagh in February and in Stewartstown, Co Tyrone earlier this month.