More than four million suspected illicit cigarettes have been seized as part of an investigation in Co Tyrone.
Five men have been arrested as part of a joint investigation by HM Revenue and Customs (HMRC), PSNI and the Revenue Commissioners.
HMRC and PSNI officers searched a farm and a private address in Co Tyrone on Thursday morning where the cigarettes, worth an estimated £1.3 million in lost duty and taxes, were found.
A suspected mobile laundering plant was also seized during the operation.
The five men are being questioned by HMRC and investigations into the seizures are continuing.
Those arrested included a 34-year-old man from Armagh, two men aged 37 and 22 from Co Monaghan and two men aged 39 and 38 from Co Tyrone.
Assistant Director, Criminal Investigation, HMRC Mike Parkinson said: "Tobacco fraud is a highly organised global crime, which costs the UK £2 billion a year in lost taxes. Co-operation with our partners across the UK, Ireland and overseas is essential if we are to tackle this problem effectively.
“Anyone with information on tobacco fraud can contact the Customs hotline on 0800 59 5000."