Authorities in Kagawa Prefecture were culling about 92,000 chickens Friday after the highly pathogenic H5 strain of avian influenza was detected the previous day.

The outbreak was confirmed at a poultry farm in Sanuki after chickens tested positive during genetic tests, making it the first bird flu case affecting livestock in Japan this season. The culling operation, which started Thursday night, was to be completed within 24 hours.

The central government's task force on the outbreak met Friday at the Prime Minister's Office, while farm ministry officials and epidemiology experts were dispatched to the site to identify the cause.