A case of highly pathogenic avian influenza(AI) has been confirmed at a duck farm in Yecheon, North Gyeongsang Province.

Authorities confirmed on Wednesday that the case, first reported Tuesday, is a H5N1 strain. It marks the first highly pathogenic bird flu outbreak at a poultry farm this fall. The last confirmed case at a farm was six months ago in April. 

Last week, a wild mandarin duck captured in Cheonan, South Chungcheong Province was found infected with AI.

On alert by the back-to-back cases, the Central Disasters Management Headquarters called the situation very serious.

The affected farm in Yecheon has 98-hundred ducks and there is no other poultry farm within a 500 meter radius. A first response team has been at the farm since Tuesday to carry out culling, access control and quarantine measures.

Officials have asked farms nationwide to thoroughly disinfect their facilities and vehicles, and citizens to avoid visiting migratory bird sanctuaries.