Dissident republicans opposed to the peace process "have to be lucky only once", the Garda Commissioner warned yesterday.
On RTE radio, Commissioner Byrne said he would "very much question the sincerity" of the "Real IRA" ceasefire.
He told Marian Finucane that the Garda was currently dealing with a small number of dissident groups.
"I cannot go into figures . . . We have been successful in dealing with them over a period, but we have to be vigilant all the time. They have to be lucky only once."
Commissioner Byrne said the Garda had foiled several attempted car bombings in the North and Britain before the Omagh bombing, which he said "should not have happened". However, the Garda "cannot guarantee 100 per cent security".
Mr Byrne said he had to accept that there were still IRA weapons dumps around the State.
"The southern command has always been seen within the IRA as providing logistical support."
He said he felt some sympathy for the RUC in coping with the changes proposed in the Patten report.
"I think I would be very hurt if somebody said the badge of the Garda Siochana must go," he said.
However, if the moves led to improvements "then I think you have to bite the bullet and accept it".
