Omagh had to be the last event of its kind, and the people responsible would be hunted down, the Taoiseach said yesterday.
After signing a book of condolences at the Mansion House in Dublin, Mr Ahern, accompanied by the Minister for Foreign Affairs, Mr Andrews, said this small number of ruthless people would have to be found.
He said the Minister for Justice, Mr O'Donoghue, and the Northern Secretary, Dr Mo Mowlam, had met the security chiefs. They were making assessments of they could best co-operate and also what new measures were desirable and which needed to be tightened up. It would take some days to work out the tactics they required.
When asked about internment, the Taoiseach repeated that all those things were being looked at. Internment was still on the statute books in this jurisdiction.
An effective method would have to be found to locate this small number of ruthless people.
Groups which had not yet called a ceasefire of any form should know there was no room in society for people to engage in this type of violence.
"Our obligation to those who died and their relatives is to make sure we push this effectively," he said.
When asked about suspects named in some newspapers and why they had not been arrested, the Taoiseach replied: "The best people to answer that are the people dealing with the operational matters.
"People can take it that those who are named and who are suspects are long under the most active surveillance and are unlikely to be the people we're chasing alone, and we're going to continue to hunt these people down whatever way we can."
Mr Ahern said every single measure open to the Garda and the RUC was being taken.
"The Garda and RUC have pointed out that in 20 years of consecutive violence, our legislation in this jurisdiction is the most repressive there is. In terms of finding new things, that's not too easy. I still hold the view that there might be new things, there might be new requirements, and there might be changes in tactics," he said.
"We're blessed with the fact that we have very good gardai and an effective RUC and they work together," he said.
He would also be continuing to have talks the British Prime Minister, Mr Tony Blair, the First Minister, Mr David Trimble, the Sinn Fein president, Mr Gerry Adams, and members of the SDLP about the peace process. "We have to keep focused on that," he said.