A number of premises have been targeted in South Kilkenny in recent days and quantities of home heating oil stolen.
At least five businesses and residential properties have been hit. Gardaí are warning people to be vigilant and to consider putting an alarm on their heating tank.
The culprits have siphoned oil from tanks and also cut the pipes and drained the oil off.
Meanwhile gardaí are investigating an incident at a windfarm at Ballybagh, Tullaroan in the early hours of Saturday morning.
The alarm was raised on Saturday evening when staff observed damage caused to a container and a diesel generator.
Anyone who saw anything suspicious in the vicinity at the time is asked to contact Kilkenny gardaí on (056) 7775000.