Since the Real IRA gun attack at Massereene barracks in which two British soldiers were killed, republican dissidents have grown steadily, rather than spectacularly, in strength.

Within 48 hours of Massereene, the Continuity IRA shot dead police officer Stephen Carroll in Lurgan. Over the past year, republicans have inflicted no further fatalities on the security forces, although they came dangerously close last month when an under-car bomb by Óglaigh na hÉireann, a Real IRA splinter group, severely injured police officer Peadar Heffron.

As Sinn Féin becomes increasingly tied into the political status quo, anti-Agreement republicans gain scope to grow in working-class nationalist communities which have benefited little from the peace process.

"Morale is high in Real IRA ranks," says one source. "It's higher than at any time in recent years."

The security services are extremely worried about the situation in east Tyrone where there have been widescale resignations from the Provisionals amid growing disillusionment with the peace process.

The level of attacks is nowhere near that of Provisional IRA activity at the height of the conflict. However, the fact three incidents linked to dissidents occurred in the past week – and the geographical spread of the activity – shows they remain a constant threat.

The device which went off outside Newry courthouse on Monday night was the first dissident car bomb to explode in the North after countless failed attempts over a decade. It means the bomb-maker has the "mix" right. The Real IRA?has claimed responsibilty for the attack.

Three days earlier, dissidents abandoned a mortar close to Keady police station in South Armagh. On Wednesday the Real IRA in Derry shot dead one of its own members allegedly involved with a drugs' gang.

Last month, the Real IRA was behind a pipe bomb attack on a British Army base in north Belfast. Although it caused minimal damage, it was the first attack the organisation had carried out in the city – where it has been previously weak – in many years.

Such attacks are training exercises for inexperienced Real IRA members. Recruits continue to be a mixture of disillusioned
ex-Provisionals and young people with no paramilitary past.