Gardaí have identified a significant number of Islamic extremists in the Republic who are a "cause for concern", according to Garda Commissioner Mr Noel Conroy.
He said gardaí were observing the individuals, and the force was liaising with police overseas who were engaged in fighting terrorism.
"You can take it that we would know quite a number of those who would cause us concern here in this country. We would be active in ensuring that we know of their movements and also, in collaboration with other countries, we would be discussing those issues," he said.
Mr Conroy was speaking after a meeting of international police chiefs at Dublin Castle yesterday. At the gathering were police chiefs from EU member-states, accession countries, applicant countries, and the heads of Interpol and Europol.
Mr Conroy said they had discussed ways in which intelligence on suspected terrorists could be gathered and shared among the international community through Europol.
He added that the bombs in the Spanish capital, Madrid, had raised concerns. However, the threat to Ireland's security from terrorists was lower than for other members of the international community.
Opening the two-day conference yesterday, the Minister for Justice, Mr McDowell, said collaboration between nations was the key to fighting terrorism.