A pollution incident in County Down has killed fish along a 5km stretch of the Kilkeel River, prompting an investigation by Northern Ireland’s environment department. Kilkeel Angling Club described it as the worst environmental event it had witnessed and warned that the loss of young fish could affect salmon and sea trout populations for years.

Trout, eels and lamprey have been confirmed dead, although the total number of fish killed is not yet known. The Department of Agriculture, Environment and Rural Affairs said it found no active discharge but is pursuing a clear line of enquiry into the pollution source; the river is an important local habitat in the Mournes.