Two men are due to appear at a special sitting of Waterford District Court tonight in connection with an international investigation into an alleged plot to murder Swedish cartoonist Lars Vilks.
A third man, who had been in custody, was released without charge shortly after 6pm. A file will be prepared for the Director of Public Prosecutions.
The men were arrested last Tuesday as part of an investigation by An Garda Síochána and law enforcement agencies in the United States and European, into alleged death threats against Mr Vilks.
It is alleged an American woman dubbed "Jihad Jane" at the centre of an alleged plot to murder a Swedish cartoonist "sponsored" a number of Muslims in Ireland on extremist websites before travelling here to meet them.
Gardaí believe Colleen Renee LaRose, who has been under arrest in connection with the alleged murder plot in the US since last October, first befriended a number of foreign nationals living in Ireland on websites.
It appears she "sponsored" them, or vouched for them, to those regulating the sites. This resulted in some of the individuals now under arrest in Ireland being given passwords to private internet chat rooms where the alleged plot to kill cartoonist Lars Vilks was discussed.
Ms LaRose, a 46-year-old US citizen, visited Ireland last August on an apparently aborted trip to Sweden. While here, she met some of the seven people arrested in Waterford and Cork on Tuesday.
Gardaí were tipped off by the FBI last October about the Irish link to the alleged murder plot. A Garda investigation was put in place aimed at covertly gathering as much information as possible on the Irish-based suspects.