The Environment Protection Authority (EPA) is investigating after hundreds of dead fish were discovered floating on the Tarwin River in Victoria.

A spokesperson for the EPA confirmed that several hundred fish were killed in the event at Berry's Creek in South GIppsland.

EPA officers were on site near Mossvale Park Road on Thursday taking water samples as part of the investigation.

A spokesperson said most of the dead fish appeared to be European carp, which are an introduced pest species.

However, there is concern that if the event is killing carp, it could be a threat to other species.

The area is known as a habitat for rainbow trout, small river blackfish, redfin, short-finned eel, southern pygmy perch and common galaxias.

The EPA notified the public of its findings via social medi

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