Toxic algae have been discovered in water samples from the Oder river on the Polish-German border where tons of dead fish have been gathered in recent days, the Polish government says.
"After further investigations, the Institute of Inland Fisheries in Olsztyn has found rare microorganisms, so-called golden algae, in water samples from the Oder river," Environment Minister Anna Moskwa said on Thursday.
A bloom of this algae could lead to the build-up of toxins that kill aquatic organisms such as fish and mussels, but are not harmful to humans, she said.
The cause of the ecological crisis is still being investigated, she added.
