Ireland's Minister for Foreign Affairs and Trade, Charles Flanagan TD, addresses the media regarding the Irish woman killed in the attack at a Tunisian resort yesterday.Photocall Ireland

Irish Foreign Affairs Minister Charlie Flanagan has warned against the possible infiltration of ISIS terrorists to Ireland, describing the threat “as a matter of great concern.”

The Fine Gael minister made the comments earlier this week regarding last week's arrest in Dublin of a man suspected of being an IS extremist. It is believed the man was attempting to travel to Syria to fight with IS.

Speaking to RTÉ news Minister Flanagan said, “This is a matter of great concern. Both the Minister for Justice Frances Fitzgerald and I keep in very close contact on this issue.”

“There are files on jihadis in Ireland, of course there are… [but] I work closely with my colleagues in the Justice Department to ensure that any information we have is shared.”

The suspect in Dublin had been under police surveillance in the days preceding his arrest, following a failed attempt to travel to Turkey on a suspicious passport. The man, believed to be in his 30s, is a Syrian national but has lived in Dublin for a number of years.

There is knowledge of ISIS sympathizers resident in Ireland. Image: Getty Images

There is knowledge of ISIS sympathizers resident in Ireland. Image: Getty Images

The man was refused entry to Istanbul on the Eastern European passport in his possession due to “irregularities” with the document and he was forced to return to Ireland. His passport was confiscated on his arrest last week, but he has since been released as Irish police failed to unearth evidence linking him to the extremist group.

A file is currently being prepared for the Director of Public Prosecutions (DPP) and a Garda source believes that the suspect will be kept under further surveillance.

"I believe it's important that we have an appropriate program of intelligence-gathering right throughout the European Union,” Minister Flanagan commented.

"That's why I'm fully supportive of the exchange of information regarding passengers on air flights.

"I would again encourage all EU states and, in particular European parliamentarians, to adopt appropriate protocols because I believe we need to ensure safety for our citizens, for people in the European Union and that will involve in the first instance intelligence and an appropriate sharing of information across a range of levels," he concluded.

The Minister also addressed the terrorist attack in Tunisia last month in which three Irish tourists were murdered, advising that the Department of Foreign Affairs does not believe people should travel to the country yet, unless it is essential.

Three Irish tourists were killed in a recent terrorist shooting in Tunisia.

Three Irish tourists were killed in a recent terrorist shooting in Tunisia.

"We are constantly keeping our security advice under review. Arising from the security situation, our travel advice will be reviewed and updated in accordance with the situation on the ground in Tunisia," he explained.

The comments come after the Turkish government promised to increase security on its Syrian border after a further ISIS bombing this week which killed 30 and injured 100.

Minister Flanagan also showed support for new anti-terrorism legislation in the UK saying that “it was key that we remain in close contact with communities in order to prevent what we call radicalization”.

“We need to remove the glamour that many of these groups have… and that involves the promotion of the rule of law and democracy… something I think we take for granted here in Ireland."

This is not the first case of an ISIS extremist coming to Ireland. Just last January a suspect was arrested in Dublin Airport following an international flight. The French-Algerian national was believed to be traveling on a fake French passport.