Some 350 jerry cans of drug waste from the production of ecstasy and crystal meth were found in a small stream in the village of Achtmaal on the Belgian-Dutch border on Monday morning.
Forest caretaker Erik de Jonge from Achtmaal was woken at around 05:00 on Monday by a report from the fire brigade about a "huge waste dump" in a stream closeby, he announced on Twitter.
Police have also reported "heavy pollution" of the soil and surface water.
Emergency services reportedly found the containers after a report from a newspaper deliverer, Dutch media report. The drug waste was scattered in several places.
Chemical waste from synthetic drugs such as ecstasy and crystal meth is very harmful to nature. Dutch police are now investigating where exactly the drug waste came from.
