The documents were unearthed in a Co Down Orange hall last week during an RUC operation aimed at two small but dangerous loyalist groups, the Orange Volunteers and the Red Hand Defenders.
Police arrested up to 12 people and have charged a number of men, which led to the seizure of several weapons, ammunition and homemade pipe bombs. Security force sources said they believed they had severely disrupted the two groups, which over the past year have been responsible for several deaths.
The RUC was commended by the Northern Ireland Secretary, Peter Mandelson, who said: "I have no doubt that this action has averted injury and possible death."
The operation led to political controversy, however, when it became known that among the material seized from the Orange Volunteers were documents which are believed to be British army issue. They are said to contain photographs, addresses, telephone numbers and other personal details on up to 400 republicans in the Belfast and south Armagh areas.
According to security sources, the lists found were several years old. This raised the possibility that they represented not a fresh leak from the army but material which had been in circulation in loyalist circles for some time. One possibility is that it could have been passed on to the Orange Volunteers by individuals in larger loyalist groups which are now on ceasefire.
The organisation does not appear to have made extensive use of the material, however. Its sporadic campaign of throwing crude but occasionally deadly pipe-bombs appears to have focused on Catholic homes in general rather than republicans in particular.
Sinn Fein demanded to know why the republicans listed in the documents, more than 300, had not been warned by the authorities that their personal details were in the hands of active loyalist terrorists.
Sinn Fein's Gerry Kelly said: "I assume that if they are British army military documentation that it's dangerous information in the hands of loyalists. The collusion between British forces and loyalists is well- documented. To our knowledge, none of the people have been informed about this. A week has passed since this emerged."
Meanwhile, there were protests from unionists yesterday following the news that a particularly notorious republican gunman had just been given seven days parole in order to get married.
Christopher "Crip" McWilliams carried out one of the most high-profile killings of the troubles when he shot dead the loyalist Billy Wright, in the Maze prison in December 1997. Two other men convicted of the same murder were among the guests at the wedding.
A spokesman for the Northern Ireland Prison Service confirmed that all prisoners nearing the end of their sentence were entitled to between 10 and 30 days parole a year.
The Ulster Unionist MP Jeffrey Donaldson said: "This episode is the latest insult to the public in terms of the way in which this whole case has been handled."Reuse content