Seven Muslims have been arrested over an alleged plot to assassinate a Swedish cartoonist who depicted the Prophet Mohammed with the body of a dog.
Al Qaida put a $100,000 bounty on the head of cartoonist Lars Vilks after a newspaper published his cartoon.
The four men and three women were detained after an investigation involving European security agencies and the CIA and FBI.
It is understood that some of those arrested hold Irish citizenship and a number are originally from the Middle East.
They were detained by gardai [the Irish police force] in Waterford and Cork in the south of the country for conspiracy to murder Mr Vilks in another jurisdiction as part of an intelligence-led probe.
The men and women arrested range in age from mid-20s to late 40s and are detained under Section 50 of Criminal Justice Act 2007 at Waterford, Tramore, Dungarvan and Thomastown Garda Stations.
They can be held for seven days.