Searches are underway of the river Shannon at the University of Limerick after a man got into difficulty earlier this evening.
The alarm was raised shortly after 6pm with members of the Fire Service, Limerick Marine Search and Rescue and gardai all responding.
Rescue 115 - the Shannon-based coastguard helicopter - also assisted in the search operation.
According to several eye-witnesses, the man got into difficulty after he entered the water with a horse at an area of the river known locally as the Sandy.
The river is being searched both upsteam and downsteam and divers have also been deployed to search under the surface.
A large number of friends and family of the missing man have gathered near the area where he was last seen.
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