Tyne Tees Environment Agency

One of the last remaining strongholds for the native white-clawed crayfish has seen around 100 die in recent weeks after developing unexplained symptoms.

Around 70 crayfish have been found dead along the River Wansbeck in Northumberland, one of the last strongholds for the species.

The Environment Agency was called to investigate what looked like oil pollution in the River Tyne in Gateshead.