Revenue officers have seized 13.3 million smuggled cigarettes at Dublin Port.
They were discovered when an unaccompanied trailer arriving from Zeebrugge in Belgium was searched.
The cigarettes have an estimated value of more than €11m (£9.4m) representing a potential loss to the Irish Exchequer of €8.9m. The brands included Marlboro Slims, Marlboro Gold and L&M Red.
A Revenue spokesperson said the seizure was part of “ongoing operations targeting the sale and supply of illegal cigarettes and tobacco in the shadow economy”.
They said inquiries were continuing.