Gavin Coney was refused bail amid claims that he was involved in a rifle firing exercise in advance of a probable attack on police.
The 35-year-old, of Gortichashel Road, Omagh, Co Tyrone, denies charges of preparation of terrorist acts, possession of a firearm with intent to endanger life or property, and attending a place used for terrorist training.
Coney and three other suspects are alleged to have been at Formil Wood, close to his home, on 30 March when 200 rounds of ammunition were fired.
It has been claimed that balloons were pinned to trees as targets, and that only 15 shell cases were recovered due to a deliberate attempt to cleanse the area of evidence.
Searches of his house led to the recovery of a legally held Walther .22 rifle, telescopic sight and silencer, four balaclavas, four identical dark jackets and bottoms, gloves and four pairs of white trainers of various sizes.
All of the items were new and unworn.
Coney insists he used the rifle for sporting and recreational purposes in the woods, using balloons and tins as targets.
He said the clothing in his attic was for Canadian colleagues who wanted protection from the elements during mining work.
Part of the prosecution case centres on a five-month surveillance operation against two co-accused.
Sharon Rafferty, 37, from Cavana Linn, Pomeroy and Sean Kelly, 46, from Duneane Crescent, Toomebridge were covertly recorded at a series of location.
The court heard the pair allegedly discussed: firearms training; the penetrative power of a .22 rifle against humans; walking up to people and putting nine rounds in them; army business; accepting resignations; attending leadership meetings; recruitment; arms acquisition; mobile police stations; and providing finance.
The prosecution claimed there was also reference to Coney and the fourth suspect - his brother Aidan Coney, 33, from Malabhui Road, Carrickmore, Co Tyrone.
They were allegedly described as being "clean" due to their lack of any criminal record.
The court lacks confidence that individual conditions of bail, or a series of conditions, taken together, would be a sufficient form of protection of the public in respect of the identified risk.
Mr Justice Maguire
Taped conversations between Kelly and Rafferty also allegedly referred to previous dissident republican attacks on police.
One of them was reported to have said "Heffron went like a dream" - an alleged description of the January 2010 car bombing in which Constable Peadar Heffron lost a leg.
It was claimed that discussions moved on to the murder of Constable Ronan Kerr, with one of the co-accused stating it was no longer a challenge to target police officers.
Coney is not accused of being involved in those discussions.
In one of the most drawn-out bail applications in recent years, Director of Public Prosecutions Barra McGrory QC appeared in person due to the complexity of the legal issues raised.
Over a two-day hearing lawyers argued about whether a suspect with a clear record should be denied bail because the type of alleged crimes carry a risk of re-offending.
Defence counsel Mark Mulholland QC stressed that Coney is still presumed innocent.
According to Mr McGrory, however, there is "chilling" evidence against the accused.
Delivering judgement, Mr Justice Maguire stressed that he was taking no view on Coney's guilt or innocence.
He ruled that his continued detention was justified on the basis of the prosecution arguments about risk of re-offending.
The judge said it was difficult to see how any bail conditions could limit the risk in the context of alleged operations by dissident republicans.
"The court takes into account the sophistication of dissident terrorist groups and the roles which an individual may play in advancing the goals of such a group," he added.