Seven million contraband cigarettes have been seized by Revenue's Customs Service as part of Operation Marble.
They were found in a 40 foot container which had arrived at Dublin Port from China via Rotterdam and were described as Ceramic Tiles.
The truck was later stopped in Co Louth and follow up searches were carried out at two private premises in Co Donegal.
It's believed the cigarettes have an estimated retail value of three million euro and represent a potential loss to the exchequer of around two and a half million euro.
Several individuals in both Co. Donegal and Co. Louth have been interviewed.