POLICE in Northern Ireland covered up nine murders committed by an informer to protect the flow of intelligence, a whistleblower claims.

The retired detective says his colleagues prevented the arrest of an Ulster Volunteer Force spy who took part in at least nine killings and ordered several more.

The accusations, made by Johnston Brown, a former sergeant, are contained in three dossiers being investigated by Nuala O’Loan, the Northern Ireland police ombudsman. Last week the whistleblower stopped co-operating with her investigators after they threatened to interview him under caution for failing to prevent the killings.

“It has made me question whether the ombudsman is the appropriate person to investigate this case,” said Brown. “I am risking my neck by exposing wrongdoing but it seemed that I was the one being put in the dock. I am putting the matter in the hands of my solicitor.”

Brown, who has 30 years service as a detective, is best known as the man whose evidence jailed Johnny Adair, the Ulster Freedom Fighters mobster known as Mad Dog. He also brought to light the allegation that the man who police believe killed Pat Finucane, the Catholic lawyer, was a Special Branch agent who had allegedly confessed to the crime but had not been charged.

The deaths in which Brown believes this informer was personally involved include:

• Tommy English and David Greer, two loyalists shot dead by the UVF during a feud with the Ulster Defence Association in October 2000.

The informer also ordered an attack in which Raymond McCord Jr was beaten to death, and then dumped in a Ballyduff quarry in November 1997. This killing was part of a dispute over drugs money. McCord’s father, also called Raymond, has since become a campaigner against paramilitary violence.

“In CID we were hearing of this man’s involvement in these murders from informants who were working around him and with him,” said Brown. “Every time we reported his actions, we were taken to task for feeding information that was embarrassing a Special Branch source. Some of the informants who told us about it also suffered for helping us.”

Questioned about Brown’s allegations, a spokesman for O’Loan said: “[We] have been talking to a former police officer in relation to a current investigation and have had discussions with him about how we could interview him at a later stage. At no time did we say we would arrest him.”

Brown’s dossiers indicate there was strong competition between the Special Branch, which gathers intelligence, and the CID, which investigates crime, for control of key agents within the paramilitary underworld.

Brown recruited three agents, each of which is the subject of a separate dossier. He believes two were “burnt off” by Special Branch for reporting crimes by fellow agents. One fled and the other was jailed. “In some cases, the loyalist paramilitaries were warned that these people were helping me,” he said.

The third informant was handed over to Special Branch in October 1991, because he was a senior figure in the UVF. His information was judged too valuable for CID to manage. “When I was handling him he saved lives: when Special Branch took control he became a killer. Once he started to take life, you could have caught this boy real handy and I tried a few times but I wasn’t allowed,” said the whistleblower.

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