Health officials in Thailand's northeastern province of Nong Khai bordering Laos, some 615 kilometers northeast of Bangkok, have culled some 2,000 chickens suspected of being stricken with bird flu, Thai News Agency reported Sunday.

A total of 230 chickens at a farm in Si Chiang Mai district of Nong Khai died of unknown causes Saturday, forcing the provincial authorities to cull some 2,000 chickens at the farm and another 60 chickens raised by villagers living near the farm, the report said.

Nong Khai's provincial governor Supot Laowansiri said the change in the weather could be one reason for the chickens at the farm to have died unnaturally.

Supot said lab tests on the dead chickens could be known within three days.

Meanwhile, the Disease Control Department under the Ministry of Public Health had announced that tests carried out during the first three weeks of January have shown that 111 persons who had been suspected to be infected with bird flu nationwide were suffering from ordinary fever or pneumonia, rather than bird flu.