Herbal cannabis with an estimated value in excess of €7 million has been seized by gardaí and Revenue and Customs officials.
325 kilogrammes of cannabis was found as part of routine profiling operations at Dublin Port.
The illegal drugs arrived in Dublin in a container from Spain.
Three men, aged 31, 47, and 49, have been arrested and are currently being held at garda stations around Dublin city.
The operation was part of ongoing joint investigations targeting the illegal activities of organised crime groups.
Officers from Revenue's Custom Service worked with gardaí from the Garda National Drugs and Organised Crime Bureau in the seizure.
Searches and investigations are ongoing.