Colin Duffy Arrest, IRA, Dissident Republicans, Real IRA
The 46-year-old is in custody accused of IRA membership and plotting to murder security force members.
Police went before Belfast Magistrates' Court on Tuesday seeking his release to carry out new interviews about separate matters.
Duffy, of Forest Glade in Lurgan, Co Armagh, was led into the dock to hear the application.
Clean-shaved and wearing a grey coat and shirt, he stood with hands in his pockets throughout proceedings.
A detective constable confirmed police wanted him for questioning.
No further details were disclosed on what is to be put to him during the interview sessions.
Duffy has been held since his arrest last December along with Alex McCrory, 52, of Sliabh Dubh View, Belfast and 45-year-old Henry Joseph Fitzsimons, of no fixed address.
Charges were brought against them in connection with a gun attack on police vehicles travelling along the Crumlin Road in north Belfast.
All three are jointly accused of conspiring to murder and belonging to a proscribed organisation - namely the Irish Republican Army.
Duffy is also accused of conspiracy to possess firearms and explosives with intent to endanger life.
A defence solicitor asked for confirmation that the police application was not linked to the alleged offences and operation for which his client is currently on remand.
The detective replied: "The matters we wish to question him about are separate."
District Judge Fiona Bagnall agreed to let Duffy be released into police custody for up to three days.
Later police confirmed a 46-year-old man was arrested by detectives investigating terrorist-related activity in Belfast and taken to Antrim police station for questioning.