Cigarettes with a street value of €11 million were seized by Customs officers last night.
The 30 million cigarettes arrived in Dublin Port on Wednesday from Singapore via Le Harve in France in a total of four 40-foot containers, according to a Revenue spokesman.
The containers, which were under surveillance, moved to locations in both Northern Ireland and the Republic before being seized simultaneously at three separate premises in Co Louth and Co Meath.
The operation, codenamed Palmal, lasted several weeks and involved various units of Customs & Excise and the Garda, with help from the French Customs Service (DNRED), HM Revenue & Customs, Belfast and the Police Service from Northern Ireland (PSNI).
In a follow up operation a joint team, consisting of Customs Officers and the Garda, raided four premises and several people were interviewed. Investigations into the smuggling attempt are ongoing both nationally and internationally, the spokesman added.