The deployment of undercover British Army troops in Ulster followed a series of high-level terrorist meetings organised by the Real IRA (RIRA) and Continuity IRA (CIRA) to co-ordinate attacks on the security forces.

Dissident terror groups have long been intent on carrying out a bomb attack and are now thought to be planning opportunistic gun attacks on individual police officers, according to security sources.

Last week Sir Hugh Orde, the PSNI chief constable, said the threat posed by republican terrorists was at a “critical” level. He admitted requesting support from the Special Reconnaissance Regiment (SRR), a special forces unit, to gather intelligence on dissidents.

Among those whose movements are being monitored by the security services is Gary Donnelly, 38, a prominent republican from Londonderry, who has previously called on the RIRA and CIRA to join forces to oppose British rule in Northern Ireland. Donnelly is regarded as a key driving force in the revival of physical force republicanism.

The SRR, which conducts intrusive and long-range surveillance, has been given responsibility for monitoring other dissidents in Armagh, Fermanagh and Derry, including RIRA bomb-makers and CIRA explosives experts. The National Surveillance Unit (NSU), an elite garda unit, has also been deployed to the border region.

The SRR, whose members have worked in Iraq and Afghanistan, was deployed in January after a car bomb weighing 300lb was abandoned inCastlewellan, Co Down. The discovery of the device, which was abandoned by RIRA near a primary school, caught the security services unaware as they had no intelligence of a pending attack. It is thought the terrorists’ target was an army base at Ballykinler.

Recent intelligence made available to the PSNI, MI5 and Crime and Security, the garda spying agency, suggests an upsurge in activity in dissident activity. The terror organisations, which have a floating membership, have stepped up recruitment and reorganised their internal security to counter infiltration by the police. They have also acquired weapons, including handguns and machinegun pistols, from criminals involved in the drugs trade in Dublin and Louth.

“The RIRA and CIRA are no longer obsessed with the notion of mounting a ‘spectacular’ bomb attack on a highprofile target,” said a security source. “It is just as likely that, sooner or later, a PSNI officer on the beat will be shot dead by a stranger who simply walks up to them and produces a gun.”

Dissident terror groups have recently extended their targeting to include civilian workers employed by the Northern Ireland Policing Board. Their aim is to force soldiers back onto the streets to support the PSNI.

The terror groups have become factionalised, making monitoring more difficult. The RIRA has divided into four groups and the CIRA has split.

“A year ago there were three terrorist groups with a defined membership. Now there are at least six, and possibly a seventh organisation which has yet to declare its existence,” the security source said. “The membership of these groups is made up of committed republicans who live in both urban and rural communities. That is why specialist undercover troops are being used to monitor suspects who live at remote farmhouses along the border and in housing estates.”

There have been more than 15 attacks by republican terrorist groups since November including shootings, booby-trap bombs, landmines and the attempted Ballykinler attack.

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