Over 200 chickens died on Tuesday at the farm, and a medical examination later confirmed the presence of the deadly H5N1 strain of bird flu.
A three-kilometer (1.8 mile) protection zone has been established around the farm. The residents of nearby villages are undergoing medical checks, the spokesman said, adding that authorities had imposed quarantine restrictions in the affected areas.
Although no cases of human-to-human transmission of H5N1 have been reported, scientists fear the virus could mutate into a strain that could pass easily between people, causing a global pandemic.
Over 200 deaths have been registered worldwide by the World Health Organization since 2003.