It follows the search of cells in Portlaoise Prison.
Two men, who were arrested as part of an investigation into an imminent threat to life in West Dublin, have been charged.
It follows the searching of two cells in Portlaoise prison, and further searches carried out at 18 locations in the capital.
A gun and ammunition were recovered, which Gardaí believe were going to be used to carry out a murder.
More than 300 gardaí were involved in this intelligence-led operation on Tuesday night, that saw a tactical team intercept a vehicle in Clondalkin.
During the search a semi-automatic glock pistol and a number of rounds of ammunition were recovered. Two men in their 30s and 40s were arrested at the scene.
The men arrested have since been charged and are due before Blanchardstown District Court today