The diesel laundering plant was capable of producing over 22m litres of illicit fuel a year, evading almost £14m in revenue.The discovery was made at an isolated farm building on Friday by HMRC officers and the PSNI.Twenty-six tonnes of toxic waste and 700 litres of illicit fuel, as well as a number of vehicles, pumps and equipment were seized.It is the second time in one week that an illicit fuel plant has been dismantled in Jonesborough.The previous Friday, customs officials and the PSNI searched a commercial address and found a laundering plant inside an agricultural shed.It was capable of producing early 20m litres of illicit fuel a year, costing the Exchequer more than £12m in potential lost revenue.During the operation, officers removed over 15 tonnes of toxic waste and almost 40,000 litres of illicit fuel, as well as a number of vehicles, pumps and equipment.Four men were arrested - two from Northern Ireland and two from the Republic of Ireland - and were interviewed by HMRC before being released on bail.Pat Curtis of HMRC said: "Every illegal laundering operation typically generates tonnes of toxic waste, involving significant safety and environmental issues. As taxpayers and local ratepayers, not only are we missing out on the stolen tax that ends up the pockets of the criminals, we are also paying the substantial clean-up and disposal costs."It is wrong that honest businesses should be undercut by criminals and those involved in making or selling laundered fuel. Buying illicit fuel not only funds crime, it supports and encourages these dangerous activities within our communities. If anyone has information about fuel fraud we would encourage them to contact the Customs Hotline on 0800 59 5000."