A suspected case of avian influenza (AI) was reported for the first time in South Korea in nearly 10 months with test results of a more detailed examination due later in the day, the government said Monday.

A suspected case was filed Sunday by a poultry farm in South Chungcheong Province where about 100 out of some 450 chickens are showing symptoms of AI, according to the Ministry for Food, Agriculture, Forestry and Fisheries.

About 40 chickens at the farm have already died with an initial test on 10 chickens with symptoms producing positive results.

"A more thorough test is underway, with the results expected to be released later in the day," a ministry official said.

The test seeks to determine whether the chickens are in fact infected with the bird virus and also whether the virus is a highly pathogenic strain of AI.

If the virus is determined to be of the H5 or H7 types, with highly-pathogenic strains, an additional test will be carried out with the results to be confirmed on Tuesday, according to the official.

Once the authorities confirm a highly pathogenic strain of AI, a temporary lockdown of all birds will be ordered, the ministry said.

The case, if confirmed, will mark the first outbreak of AI since May 16. (Yonhap News)