Over 150 fish were killed in an incident on the Ballinagh River in Co Cavan last week.
Environmental and Fisheries Officers from the North-Western River Basin District were alerted to the incident by a member of the public last Tuesday evening.
Inland Fisheries Ireland is investigating a fish kill at the Ballinagh River on the evening of the 19th of July, and water samples have been taken for scientific analysis.
IFI estimates over 150 fish were killed, including brown trout, stickleback and minnow.
As investigations are ongoing, IFI says it is not in a position to comment on the cause of the fish kill.
Dr. Milton Matthews is the Director of the North-Western River Basin District with IFI.
He thanked the public for its ongoing support in reporting suspected cases of water pollution and fish kills and said he was "grateful to the person who reported this incident to us so promptly".
Dr Matthews added that this "enabled our team to take immediate action and start the investigation without delay", which is "very often critical in determining the underlying cause of fish kill events".
Inland Fisheries Ireland has a new confidential, 24-hour hotline number on 0818 34 74 24 to allow the public to report any sightings of fish kills or suspected water pollution.
