An Algerian man who's an Irish citizen has pleaded guilty in the US to conspiring to provide material support and resources to terrorists.
53-year-old Ali Charaf Damache was indicted on two charges in 2011.
He and others have been accused of conspiring to recruit people to 'wage violent jihad' in Europe and South Asia.
He was extradited to the US from Spain last year, with both Spanish and Irish authorities said to have assisted in the US investigation.
US Justice Department officials say he's agreed to a 15-year prison sentence as part of his guilty plea.
Damache will be returned to Ireland or Algeria after his prison term, and authorities say he has waived his right to appeal.
FBI Assistant Director in Charge William F Sweeney said: "Damache knowingly and willingly conspired with others to wage a violent jihad overseas, actively supporting the very ideals that allow terrorism to thrive worldwide."
He will be formally sentenced in October.