The PSNI is concerned that the IRA has long-range plans in place for the resumption of violence, reports Jim Cusack, Security Editor
No senior member of the Northern Special Branch attended this week's high-power conference between the Police Service of Northern Ireland and the Garda in Templemore, Co Tipperary this week. They were tied up in what are said to be frantic efforts to trace the whereabouts of files identifying 250 Special Branch detectives whose jobs are the most sensitive and important in terms of counter-terrorism.
Sources say the notebook taken from Castlereagh Police Station on St Patrick's Day contain the officers' names and addresses, and the code names by which they were known to their informants.
The PSNI has stated that the identities of informants were not compromised in the raid. But other sources have said that the raiders took documents on which intelligence from the informants is recorded. If these slips are linked to the codebook, it is possible that the raiders could match the information to identify the informants.
That situation, a Northern police source said, represented a crisis in intelligence-led anti-terrorist policing. One source compared the seizure to the Allied Forces' seizure of the German military's Enigma encryption machine in the second World War. It is understood that Special Branch officers' families have begun moving home.
The concerns for the safety of the police and their families is heightened by intelligence reports which have been reaching the PSNI that the IRA remains very active procuring arms and military material, training and targeting police, government and political figures.
The PSNI is now concerned that the IRA has in place long-range plans for a resumption of violence if it decides that there are no further political gains to be made.
Gardaí differ slightly on this point and feel the IRA is still intent on adhering to the peace process. However, senior Garda sources say that the PSNI and previously the RUC has continued to gather high-grade intelligence about the IRA and that they were prepared to accept the PSNI assessment.
The investigation into the break-in at Castlereagh has now become the highest priority for the PSNI.
At first it had been thought that a rogue police or military element or undercover soldiers working to an unknown agenda carried out the robbery.
Initial suspicion is understood to have been directed towards one or two undercover police whose technical expertise and knowledge of the interior layout at Castlereagh would have allowed them access to the most sensitive areas.
Also, the raiders displayed techniques in stunning and overpowering the sole detective on duty which are remarkably similar to those taught to undercover police and soldiers.
The officer was also bound with disposable restraints of the same type used by the Army and Police. One of the three raiders also tended to the prone officer, checking his pulse and massaging his hands and feet to ensure his circulation was not restricted by the cuffs.
Police sources said initially it would be unlikely that the IRA would show such consideration. to a police prisoner.
However, as the PSNI investigation has progressed, attention has switched to a number of civilian staff who could have helped a break-in.
The complex is undergoing construction and the Special Branch nerve centre was in temporary accommodation and vulnerable.
It is understood that in recent days, the PSNI Special Branch has gained stronger evidence of collusion between a civilian employee and the IRA.
Meanwhile, Sinn Féin continues to deny any republican involvement in the raid.