Authorities began culling some 50,000 chickens after a bird flu outbreak at a farm in the northern Iwate region.
It is the 19th bird flu outbreak of the season in Japan, the agriculture ministry said.
The latest farm reported increasing deaths of fowl, and test results confirmed Sunday that bird flu was the cause, the ministry added.
It prompted the culling of 50,000 chickens there, the regional Iwate government said.
Iwate also banned the movements of 170,000 birds kept at two other farms within a 3km radius.
Some 3.8 million birds kept within 10km of the infected farm are to stay inside the zone for now.
On Thursday, another farm in Iwate and a firm in the central Aichi region were hit by the virus and began killing their 120,000 and 147,000 birds respectively.
On Dec 29, an outbreak was confirmed at a farm in eastern Ibaraki, resulting in the killing of 1.08 million birds there. — AFP
