Sixty-four people have been arrested as part of Operation Thor in the Kilkenny and Carlow areas.
Sixty garda checkpoints were carried out over the course of the day, and 29 houses and one business premises were searched in Kilkenny city, and the Urlingford and Castlecomer areas.
Heroin, ecstasy, cannabis, cocaine and amphetamines worth an estimated €34,000 were seized.
Gardaí discovered a cannabis grow house in Castlecomer with plants worth an estimated €4,000 seized.
A handgun was also recovered during a search of a house in Kilkenny city.
Twenty-two of those arrested were detained for a range of matters including theft, assault, fraud, misuse of drugs and burglary offences.
Garda say nine of those arrested appeared before courts in Kilkenny and Carlow.
Thirty-three were arrested on foot of committal and penal warrants.
More than 130 garda were said to have been involved in the operation, along with 50 garda students from Templemore.
Chief Superintendent Dominic Hayes said the objective of the operation was to "disrupt criminals living in and travelling through the Kilkenny/Carlow Division".