MOSCOW: Russian authorities have declared a state of emergency after more than 20,000 tons of diesel fuel seeped into a Siberian river sparking concerns from environmentalists. The World Wildlife Fund environmental group on Tuesday praised local efforts to contain the spill with a floating dam, blocking dangerous pollutants from flowing into a lake near the Arctic city of Norilsk. Satellite images published by the WWF showed large red spillages in the Ambarnaya river and local residents posted videos on social media showing polluted water.