Some 36 Dutch chicken farms are implicated in a German inquiry into fraud with organic eggs, the public prosecution department told broadcaster Nos on Monday.

German officials suspect hundreds of farms have been labelling eggs as organic even though they did not keep the chickens in organic conditions and kept too many birds in the same space.

The Dutch firms are suspected of supplying laying hens to the German firms using a double book-keeping system and fake bills. This allowed the German firms to show they did not have as many chickens on their farms as they actually did.

German officials have asked their Dutch colleagues for help with the investigation, Nos said.