There was no suggestion or evidence that a serving garda was involved in the alleged surveillance of two RTE journalists who investigated overcharging of customers by National Irish Bank, the Minister for Justice, Mr O'Donoghue, told the Dail.

He was responding to Fine Gael's justice spokesman, Mr Jim Higgins, who said that a magazine claimed that the man suspected of keeping watch on the RTE journalists was well-known to the gardai.

"He was one of the most prolific snoops in the country, and was not a member of the Army Rangers but a current serving detective," Mr Higgins said, quoting from the magazine.

The Minister said the suggestion that a serving garda was involved in the alleged surveillance "is a very serious matter". He had been informed by the gardai that they were not aware of such reports and "at no stage during the investigation was there any mention or any suggestion" that a serving garda was involved in such surveillance.

Mr O'Donoghue said a senior garda investigating the allegations of surveillance interviewed the two journalists. Neither journalist was able to provide direct evidence of surveillance taking place, Mr O'Donoghue said. "The garda could not find evidence that the surveillance was taking place. Neither, let it be said, could they find evidence that surveillance was not taking place."

The Garda investigation remained open but no evidence had come to light "which would enable the gardai to submit a file to the Director of Public Prosecutions seeking directions for prosecutions". Mr O'Donoghue added, however, that "if anyone has any information in relation to this aspect of the matter, I would exhort them to contact the gardai immediately".