Health authorities said Saturday they've confirmed a case of avian influenza (AI) in a chicken at a southern region farm and another in feces of migratory birds in the central part of the country, amid ongoing quarantine efforts to contain the bird flu virus since earlier this month.

The Ministry of Agriculture, Food and Rural Affairs said it will try to determine whether the infected poultry contains the highly pathogenic H5N8 strain of the virus and will announce its findings on Sunday.

It said the chicken had been raised at a farm in the county of Buyeo, South Chungcheong Province, about 195 kilometers south of Seoul, along with some 22,000 others.

Later on Saturday, officials in Gyeonggi Province said feces recovered from around Sihwa Lake in Hwaseong, just south of Seoul, also contained AI.

They said they could conclude by as early as Sunday if the strain is the highly pathogenic kind.

The province has designated the area within a 10-kilometer radius of the lake as a quarantine zone, restricting entries of poultry and vehicles, officials said.

The confirmation from the poultry farm in Buyeo is expected to expand the scope of precautionary culling to cover chickens. Only ducks had been slaughtered as a preventive step after the highly pathogenic strain of bird flu was found among a group of migratory birds found dead on Jan. 17 at a reservoir near affected farms in North Jeolla Province.

Authorities believe they may have been the carriers of the virus. (Yonhap News)