Efforts are under way in Westmeath to locate the source of an oil spill in the River Shannon over the weekend.
A number of animals, including cormorants and cygnets were covered in oil in the incident on the River Shannon in Athlone at an area known locally as the "Big Meadows".
A spokesperson for Athlone SPCA said some of the birds have been taken for special cleaning to an animal sanctuary in Kildare.
Westmeath County Council is investigating the source of the oil spill.
In a statement, the council said it has technical personnel on site to try to confirm the source of the pollution, and determine the next steps.
"We would like to acknowledge the very helpful assistance of angling and wildlife volunteer groups who have been able to reduce the impact of this incident on the local wildlife," the statement added.
A spokesperson for Inland Fisheries Ireland confirmed it is investigating the oil spill but said it could not confirm as yet if any fish have been killed.