A 48-year-old man who died after eating his neighbor's sick chickens had bird flu, making him the 13th person confirmed to have died from the disease in Thailand, the prime minister said Thursday. Initially, authorities said the man, who died Wednesday, had tested negative for the virus. But on Thursday, Prime Minister Thaksin Shinawatra said new lab results confirmed the bird flu diagnosis. The man, Bang-on Benphat, was hospitalized with pneumonia-like symptoms on Sunday, shortly after he cooked and ate his neighbor's dead chickens. Officials said the birds had died of abnormal causes but were not tested for bird flu. But other chickens in the village in the Phanom Thuan district of Kanchanaburi province tested positive for bird flu, said Dr. Thawat Suntrajarn, director-general of the Department of Communicable Disease Control.