A company linked to Ireland West Airport Knock has been fined €10,000 for the illegal use of green diesel, according to media outlets.

The firm in question, Connaught Airport Development Company Limited – which manages the airport – pleaded guilty to four counts of illegal use of green diesel in vehicles, according to RTÉ.

The vehicles in question includes: a small passenger bus; a fuel tanker; a de-icer; and a snow plough.

Held in Tubbercurry District Court, it was apparently stated that the firm co-operated with officers employed by the Office of the Revenue Commissioners and accepted that green diesel was being used in 14 vehicles at the airport.

Officials are believed to have claimed in evidence put forward that they were not aware the practice of using green diesel was illegal and that they had “always” used the fuel.

The defence also told the court that there had been no attempt to conceal the use of the marked fuel in the airport, adding that management believed that, as the airport vehicles were not on public roads, the use of such fuel was permitted.

All use of green diesel in the airport has since ceased, the defence purportedly said.

With a maximum fine for each count amounting to €5,000, Judge Kevin Kilrane convicted the company on all four counts, fining the company €2,500 for each count.