Four men are in custody following the discovery of viable bomb outside Ballymahon, Co. Longford.
The find is part of an ongoing investigation into the activity of dissident republicans.
Army bomb disposal experts made the device safe after they were called to the R392 at Forgney on the Longford Westmeath border last night when Gardaí found a suspected improvised explosive device in a car.
A cordon and road closure was put in place and the team arrived on site shortly after 9pm, before declaring the scene safe at around half ten without the need for a controlled explosion.
Gardaí later arrested four men, ranging in age from late 20s to late 40s, who are now being held at Longford Garda Station under Section 30 of the Offences Against the State Act.
A house that was searched in a follow up operation has been preserved for a technical exam while components of the bomb have been handed over to Gardaí for examination.