Garda Commissioner Justin Kelly has described the discovery of a sophisticated bomb in a car near the Northern Ireland border as an "extremely significant" seizure.
The explosive device was found after gardaí stopped a vehicle on the N2 south of Carrickmacross, Co Monaghan, during an intelligence-led operation targeting dissident republican activity.
The Army Explosive Ordnance Disposal (EOD) team was called to the scene to make the device safe before it was removed for forensic examination.
Speaking on Friday, Commissioner Kelly said the bomb was fully assembled and ready for use.
"What I will say certainly is it was a significant explosive device. So certainly not just the seizure of components or pieces. This was an explosive device and it would have or could have potentially caused significant damage."
Gardaí believe the device was intended to be used as an under-car bomb in an attack in Northern Ireland. It reportedly contained a power unit, detonator and military-grade explosives.
Commissioner Kelly said the operation was not a routine traffic stop but was carried out following intelligence gathered by the Special Detective Unit.
He also warned that while the number of dissident republicans remains small, they continue to pose a threat.
"There's a small minority of these individuals, I would describe them as radicalised republicans, and this is a threat that we're going to continue to face for some time in An Garda Síochána."
A woman in her 20s, who was driving the vehicle, was arrested under Section 30 of the Offences Against the State Act and remains in custody. A man in his 40s has also been arrested and is being questioned by gardaí.
Minister for Justice Jim O'Callaghan described the discovery as "very worrying" and said it highlights the continued threat posed by dissident republican groups.
He also praised the work of gardaí and the Defence Forces in ensuring the bomb was safely recovered before it could pose a danger to the public.
The operation was carried out in close cooperation with the PSNI, with Commissioner Kelly confirming that both police services continue to work together to combat dissident republican activity.
