Avian flu has turned up in preliminary tests at a poultry farm in Tanba, Kyoto Prefecture, that has seen some 28,000 of its chickens die over the past week but neglected to alert authorities to the possibility of an outbreak of the disease sweeping Asia.
Authorities said Friday that final confirmation would not come until early next week.
If confirmed, it would be the third such case in Japan since an outbreak at a chicken farm in Yamaguchi Prefecture in mid-January. Until then, no case of bird flu had been reported in Japan since 1925.
The case of a dead chicken found at an elementary school in Nagano Prefecture was confirmed Friday not to be a case of bird flu.