Army rangers are not trained in electronic surveillance techniques such as those alleged to have been used against two RTE reporters, an Army spokesman said.
Responding to a report that exRangers now working for private security firms may have been involved in telephone surveillance against the reporters who broke the National Irish Bank scandal, the spokesman said: "If the story is true, it's not a skill they picked up from us."
He added there were "only a very small number" of former soldiers from the Army's elite unit now working in private security firms, but admitted there were no special restrictions on the kinds of employment ex-Rangers could take up.
"We would be disappointed if any of them were putting their training to inappropriate uses. But the sort of equipment needed for surveillance of mobile phones and such is sophisticated, expensive stuff, and we don't have it. It's a huge leap of imagination to think they learned that sort of thing from us."
Meanwhile, the Labour Party said the allegations highlighted the urgent need for regulation of the security industry. The party's justice spokesman, Dr Pat Upton, said there was great public concern about a sector which now involved 400 companies employing 10,000 people, with an estimated annual turnover of £200 million.
He urged the Government to act on the report of a consultative group published last January. "It came down strongly in favour of a regulatory framework which would include a licensing system for the industry, fitness to practise hearings, on-site inspections and a complaints procedure. It is now the job of John O'Donoghue, Minister for Justice, to take immediate action to implement these recommendations."
Dr Upton also called for a Garda inquiry into the allegations of illegal surveillance. "It would be disgraceful if, at the conclusion of this saga, the major casualties turned out to be the people who helped bring this behaviour to light."
The National Union of Journalists said that, if illegal surveillance had been used, those responsible should be investigated and prosecuted, if necessary. The union's Irish secretary, Mr Eoghan Ronayne, said the allegations raised several "huge questions," but he was particularly worried that a lack of security surrounding mobile phone records could be exploited to identify journalists' sources.
The Socialist Party TD, Mr Joe Higgins, said it would be an "extremely disturbing and sinister" development if the journalists who exposed the NIB scandal were subjected to electronic and physical surveillance.
"It is bad enough that some banking institutions have been acting with the arrogance of a second national taxation authority in the State," he said.
