Cannabis believed to be worth €363,000 was seized in Dublin, leading to the arrest of three persons.
Revenue officials searched residential properties in north Dublin and discovered around 18.1kg of herbal cannabis.
A man in his 20s was arrested on Wednesday and has been charged.
A man and woman in their 30s were arrested on Friday and are both being detained under section 2 of the Criminal Justice (Drug Trafficking) Act 1996 at a Garda Station in north Dublin.
Investigations into the matter are ongoing.
The seizures were made as part of an intelligence-led joint operation involving Revenue’s Customs Service, the Garda National Drugs and Organised Crime Bureau and Garda District Drug Units attached to Ballymun, Balbriggan and Coolock Garda stations.