Concern's being expressed following what's been described as a major fish kill in the Owenreagh River near Dromore in Co Tyrone.
West Tyrone MLA Catherine Kelly says having spoken to the Loughs Agency, it's been confirmd to her that a slurry lagoon failed, releasing over 100,000 gallons into the river.
Up to fifteen mile of river could be affected, including the Drumragh and the Strule. There is extensive damage and a huge number of fish killed between Dromore and Omagh.
The Lough's Agency are taking remedial action.