It comes as gardaí question two men in Waterford, also in connection with dissident activity.
At Omagh Magistrates Court today, Daniel John Turnbull from Strule Park in Omagh was accused of conspiracy to murder and firearms offences.
The 30-year-old was one of four arrested when the PSNI, targetting dissident republicans, stopped a car near Cookstown in Co Tyrone on Monday evening and recovered a gun and ammunition.
The man was remanded in custody.
Meanwhile, two men are in garda custody in Waterford in connection with dissident republican activity.
Both were detained last night after gardaí stopped and searched a car on the Dungarvan Road.
Army bomb disposal experts were alerted after a pipe bomb was found in the vehicle.
No controlled explosion was carried out and the scene was declared safe in the early hours of this morning.