Two men and a woman were being questioned today after gardaí seized a sawn-off shotgun and ammunition.
The three, all in their twenties, were arrested last night after detectives stopped and searched a car in Co Cork.
The checkpoint had been mounted as part of Operation Anvil at Garryoutragh, Mogeely and the car stopped shortly after 10pm.
Gardaí said a sawn-off shotgun, cartridges and a number of balaclavas were recovered in the search.
A man and woman were taken to Middleton garda station, and the second man is being held in Fermoy.
All three are being questioned under section 30 of the Offences Against the State Act.