A major fish kill is being investigated on an environmentally sensitive river in Co Cork in which at least 5,000 fish have died.
The investigation is being conducted by Inland Fisheries Ireland (IFI), the State agency responsible for the protection and conservation of freshwater fish and habitats.
The affected river is the River Allow, a tributary of the Munster Blackwater catchment, and the pollution incident occurred near Freemount in the north of the county in an area designated as a Special Area of Conservation.
Uisce Éireann has a water treatment plant in Freemount, and said it is investigating a reported spillage at the plant.
IFI officers are still attempting to determine the scale of the fish kill and have observed dead fish in the river 4km downstream of the suspected source location.
Uisce Éireann said it has engaged with IFI and has also notified the Environmental Protection Agency.
Species of fish discovered dead include juvenile Atlantic salmon, brown trout, lamprey, eel, stone loach, roach, and dace.
The river also supports a population of freshwater pearl mussel, as well as being an abundant salmon and trout habitat.
Water samples have been taken from the river to gather evidence of the discharge, the source point of contamination, and advance any potential prosecution, according to IFI.
