This article originally appeared on Time.com.
The world’s largest nickel manufacturer, Norilsk Nickel, said it was responsible for turning a river in the Siberian town of Norilsk into a lurid shade of red last week.
On Sept. 7, Russia’s environment ministry suggested a pipe leakage from a factory owned by Norilsk Nickel may have resulted in the discoloration of the Daldykan river in the Russian Arctic.
The company initially denied that the pollutants originated from one of its plants.
#Norilsk, northern #Russia: the site of copper & nickel #mining & #environment|al degradation pic.twitter.com/2s6kRXPsql
— Alex Kokcharov (@AlexKokcharov) September 7, 2016
According to the BBC, the company said that a filtration dam was compromised on Sept. 5 after heavy rains caused it to overflow into the river.
Although the company denies any danger to people or wildlife, Greenpeace Russia activist Alexei Kiselyov told Agence France-Presse that it was too early to assess the impact. “You can’t just say that it’s no big deal,” he said.
Kiselyov accused Norilsk Nickel of hindering investigations by controlling access to the affected areas, making it difficult to inspect pollutants originating from their factories.