Thousands of dead mussels have been discovered in Kokemäki river in western Finland, with possible links to earlier spillages of heavy metals and oil in the river.
The deaths near Ruskilankoski were reported to the Centre for Economic Development, Transport and Environment (ELY) on Monday and divers are now collecting mussels to have them tested for heavy metals and organic hydrocarbons.
In July 2014 , some 66 tonnes of nickel leaked into the river from a Norilsk Nickel mine in Harjavalta, causing the death of millions of mussels several weeks later.
At the end of last year some 50,000 litres of light fuel oil leaked into the Kokemäki river from a heating plant operated by power firm Pori Energia.
ELY said it will examine whether one of those leaks is responsible for the mussel deaths and will report its finding after Easter.