A seizure of 1.1 tonnes of cannabis resin was made thursday night, according to gardaí.
During a joint Garda and Customs operation, the discovery was made at an industrial premises in Dunboyne, Co. Meath.
This seizure, subject to analysis, has an estimated street value of €6.6 million.
A man in his 30s was arrested close to the scene and is being held at Blanchardstown Garda station under Section 2 of the Drug trafficking Act.
Investigations are ongoing.