Illegal fuel and 12 vehicles have been seized by HM Revenue and Customs (HMRC) officers in Londonderry.
The van and one other vehicle were seized by officers on the Buncrana Road on Wednesday.
Both vehicles had been adapted to carry smuggled fuel, and 1,600 litres were recovered.
Ten other vehicles were also found to contain either red or green diesel in the tanks, resulting in the seizure of 3,000 litres of fuel.
The seizures were part of a joint operation between HMRC, the PSNI and the Driver and Vehicle Agency.
During the operation 14 vehicles were found to have no tax. Nine of them were clamped.
Brian Dixon from HMRC said fuel smuggling was not a “victimless crime”.
“The criminals involved in the transportation of smuggled fuel care nothing for the safety of other road users,” he said.
“The vehicles used are unsafe, and the dangers they pose to anyone in the vicinity show a total disregard for public safety.
“HMRC takes the unfair sale and use of smuggled fuel very seriously.
“Genuine businesses are already facing difficult times and it is wrong that they should be undercut by these criminals.”
Red diesel is for use in agricultural machinery and not for use in road vehicles. Green diesel is the Republic of Ireland equivalent to red diesel.