John Downey, who was arrested at his Donegal home on Monday in relation to a 1972 bombing which killed two members of the UDR, is to fight extradition to the North.
The 66-year-old appeared before the High Court on Tuesday in relation to an extradition warrant.
The court heard he was arrested at his home in Ards, Creeslough on Monday under a European Arrest Warrant, RTÉ reported.
His extradition was requested by the PSNI for questioning in connection with two counts of murder and one count of aiding and abetting an explosion.
Lance Corporal Alfred Johnston and Private James Eames died when a device exploded in a car they were checking on the Irvinestown Road in Enniskillen in 1972.
Sergeant Jim Kirwan said Mr Downey surrendered his passport and had fully co-operated with gardaí.
Mr Downey's lawyers said he would be contesting the application to extradite him to the north.
Ms Justice Aileen Donnelly said she would hear the full extradition application on November 23.
She remanded Mr Downey in custody and said she would hear a bail application on Thursday.