DENIS DONALDSON, the British mole in Sinn Fein, was cast adrift by his handlers after they suspected that he had become a double agent spying on the Stormont administration for the IRA.

Donaldson’s role was uncovered by a second low-level informer who was reporting to the PSNI Special Branch.

A security source said: “Denis was caught with his fingers in the till. He wasn’t telling his handlers everything he was up to.”

The search is now likely to start within the republican movement for
the second mole and nobody will be above suspicion. Two years ago Freddie Scappaticci, deputy head of the IRA’s internal security division, was unmasked as a British agent known as Stakeknife.

The second Stormontgate agent gave the police information that led them to a stash of documents and a computer containing IRA intelligence gathered at Stormont. It included the details of thousands of prison officers, dissident republicans, civil servants and even a well known lawyer with the words “must go” written beside her name.

The tip-off came within a few days of the IRA raid on Special Branch headquarters in Castlereagh on March 17, 2002. The code names of scores of Special Branch detectives and clues to the identities of informants were seized by the IRA.

Larry Zaitschek, a former chef at Castlereagh police station, was suspected of helping the raid. Donaldson had met Zaitschek in New York when he was the Sinn Fein representative in America, and encouraged him to come to Northern Ireland. Zaitschek returned to New York shortly before the raid and now denies all involvement in it.

The papers stolen at Castlereagh were taken first to Derry and then to the republic. Police believed that the Stormont papers were destined for the same IRA network. A surveillance operation, codenamed Torsion, was launched, involving telephone taps bugging, surveillance and the use of agents.

The IRA documents involved were recovered with the help of the informant and then copied and returned to their hiding place.

Operation Torsion culminated on 4 October 2002 in a raid on Donaldson’s home and a follow-up search at his office in Stormont, where three computer discs were seized.

Two days before the raid Donaldson had met his Special Branch handlers. He had told them nothing of the spy ring and they did not warn him that he was at the centre of an investigation.

Donaldson got no protection from Special Branch or MI5, to whom he had also reported on occasions, because he had not passed on information about the documents. Donaldson, his son-in-law Ciaran Kearney and William Mackessy, a former civil service messenger at Stormont who now works for Sinn Fein’s Gerry Kelly, were all charged.

A decision was taken to drop the case against them when the prosecution was refused Public Immunity Certificates that would have protected the agents’ identities. By that time, Sinn Fein’s suspicions had been roused that one or more informants were involved.

On Tuesday, Donaldson was met by his handlers for the first time since his arrest and told his life was in danger.

The ensuing political row is unlikely to subside, even though the British government and Sinn Fein are both eager to draw a line under the affair.

Lord Goldsmith, the British attorney general, has told the SDLP, DUP and UUP that he was satisfied that there was ample evidence on which to base a prosecution of Donaldson, Kearney and Mackessy but that it had been withdrawn in the public interest. This is normally a code for the protection of life or of an important intelligence interest.

Matters are unlikely to rest there, with the Ulster Unionists demanding a public inquiry, the DUP and SDLP seeking more information, and Bertie Ahern asking the British government for clarification.

David Trimble, the former Ulster Unionist leader whose administration was toppled by Stormontgate, said: “It’s the republican movement that’s in a crisis today. They have discovered that a person who was at a very senior level within Sinn Fein in fact was operating as an agent for over 20 years.”

The SDLP is suggesting that Adams should resign. Eddie Espie, the party’s vice-chairman, said: “Only a few days ago, Adams was happy to appear alongside Donaldson on the steps of Stormont. Now it transpires that Adams was singing the praises of an arch-British agent. The buck stops with him. The only option now open is for Adams to resign.”

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