Customs inspectors have seized 10 million black market cigarettes in a 40ft container in Cork port.
The tobacco, worth 4.2 million euro in the shops and if sold on the streets would have cost the Exchequer 3.5 million euro, were labelled 'Paper Stationery'.
Customs said its officers were acting on intelligence when they intercepted the load from Malaysia.
The cigarettes were branded "Club 88" which inspectors call illicit whites as it is the first time this type of tobacco has been seized in Ireland.
Customs said the European Anti Fraud Office (Olaf) played a pivotal role in an international operation to seize the load.
To date in 2011, 54m cigarettes with a retail value of approximately 22.5m euro have been seized by Customs.