Massive fish deaths in the Oder River that borders Germany and Poland which have been occurring since late July was finally addressed by the government on Friday, with the cause of the deaths still unknown.

German Environment Minister Steffi Lemke commented on the situation after massive amounts of fish were found dead in the Oder River due to toxic substances in the water, saying that the government is still attempting to find a cause for the deaths, according to Reuters

“An environmental catastrophe is in the offing,” Lemke said. “All sides are working flat out to find the reasons for this mass die-out and [minimize] potential further damage.”

The deaths were first detected near the Polish town of Olawa in late July, before spreading through to the German state of Brandenburg, where a warning was sent out for civilians to avoid the water lest they be infected by the toxic substance in the water, CNN reported. 

“The scale of this pollution is very big. So big that the Oder may take years to return to a fairly normal state,” Polish Prime Minister Mateusz Morawiecki said on Friday. “It is likely that enormous amounts of chemical waste have been dumped into the river.”

Germany has criticized Poland for its supposed breakdown of communication after there was a reportedly long delay between the discovery of the deaths in Poland and the Polish government informing them of the situation. 

“The chains of communication between the Polish and German sides did not work in this case,” Brandenburg environment minister Axel Vogel said.

Morawiecki has already fired the country’s national water management authority head Przemyslaw Daca and general environmental inspectorate Michal Mistrzak for how long it took for them to react to the situation, and they are apparently working with German authorities to get to the bottom of it. 

Environmentalists from Germany have criticized the mass deaths, with some of them blaming it on the slower water conservation efforts in the country, as well as a lack of communication between Poland and Germany regarding the situation, Deutsche Welle reported. 

“This ecological catastrophe would not have been of such magnitude if the German and Polish authorities had worked together more intensively,” Antje von Broock, director of the German Association for the Environment and Nature Conservation, said. 

milos-prelevic-65busv7PmzM-unsplash Massive fish deaths in the River Oder, which borders Germany and Poland, continue to devastate the channel as toxic substances appear to have been found in the water. This is a representational image. Milos Prelevic/Unsplash.