South Korea's agricultural ministry said Wednesday it is investigating two suspected cases of highly pathogenic bird flu from local farms, amid growing concerns that the disease may penetrate deeper into the local poultry industry.

Authorities are investigating the two suspected cases from ducks farms in North Jeolla Province and South Chungcheong Province, according to the Ministry of Agriculture, Food and Rural Affairs.

Since identifying the first infection in late November, South Korea has reported 33 cases of the highly pathogenic H5N8 strain of bird flu from local farms.

Gyeonggi Province accounted for nine cases, followed by South Jeolla Province with eight.

As of Wednesday, local authorities have culled more than 10 million birds.

All poultry within a 3-kilometer radius of infected farms are culled.

The ministry said the domestic market for poultry products nevertheless remains stable, pointing out that the culling of birds had only a limited impact on supply.

Meanwhile, 44 bird flu cases in wild birds have been confirmed since late October. (Yonhap)