Police believe the Continuity IRA was behind a foiled mortar bomb attack in the Lurgan area, the High Court has been told.
Two of three men charged over the incident were applying for bail.
Sean McConville, 21, from Lurgan and Gary Toman, 22, from Craigavon are accused of conspiracy to murder and possessing explosives.
Both were refused bail. The court heard a fourth man being sought by police is believed to be in the Irish Republic.
The court was told four men were arrested last March after police stopped a car following a report of suspicious activity.
They were released without charge but were re-arrested a week later after police found a mortar tube and warhead containing Semtex about a mile from where their car had been stopped.
Mr McConville, from Kilwilkie Road, and Mr Toman, from Drumnamoe Avenue, Craigavon are also charged with having articles useful to terrorists.
Lord Chief Justice Sir Brian Kerr refused bail but said if full forensic reports were not readily available there could be fresh applications due to the length of time the defendants had been in custody.