The agency does not know how the crayfish became infected
A colony of an endangered species of crayfish which lived in a Staffordshire river has been wiped out.
The Environment Agency reported that hundreds of rare white-clawed crayfish in the River Manifold near Wetton Mill had been killed by crayfish plague.
The disease is carried by the American Signal crayfish, a species introduced to the United Kingdom which can resist the plague.
A spokesman said any remaining crayfish downstream would suffer the same fate.
Agency spokesman Phil Wormauld said it was a tragedy for one of the country's rare native species.