SAGA PREFECTURE, Japan — The culling of 69,000 chickens began Saturday night in southwestern Japan after some dead chickens at a poultry farm in Saga Prefecture were found to be infected with a highly virulent strain of bird flu.

After about 40 chickens were found dead Saturday at a farm in the town of Kohoku, the prefectural government conducted genetic tests and confirmed the presence of a highly pathogenic avian influenza virus, the government said.

Since November, bird flu has been detected at poultry farms in six prefectures in Japan, including Japan’s northernmost prefecture of Hokkaido and Miyazaki in southwestern Japan.

In Saga, about 73,000 chickens were culled in January 2015 after a bird flu outbreak was confirmed.

—Kyodo