Dozens of Friesian farmers are implicated in a fraud involving the handling of manure, news website Nu.nl reports.

A 56 year-old farmer from Tietjerksteradeel is suspected of supplying farmers with fake manure transport papers and making up false bills, the website said.

During a search of the man’s house on Thursday, police and officials from the product safety board NVWA confiscated various computers and administrative papers. The investigation goes back to 2014 and 2015.

The amount of manure a farmer can use depends on the size of his land. The bigger the area the more manure he is allowed to spread. A surplus of manure has to be removed and processed for a fee.

Officials think that farmers wanting to avoid paying the fee have illegally used too much manure on their land. This leads to high concentrations of phosphate in the ground which can affect the quality of the ground water.

No arrests were made but the farmers will be facing a hefty bill for unpaid fees.