REVENUE and Customs officers have smashed three fuel laundering plants with the capacity to produce 26 million litres of illicit fuel a year.
The intelligence-led operations discovered the plants in Cullaville, south Armagh.
Customs say that the plants had an automated filter system for bleaching agricultural diesel.
The potential total loss to the public purse would have been around £18 million.
No arrests have been but tonnes of toxic sludge have also been found which will now to be disposed of to protest the environment.