Local tests showed a 7-year-old girl has died of bird flu, a health official said Friday, the latest in a series of cases that are putting Indonesia on pace to become the world's hardest-hit country.

The World Health Organization has yet to confirm the death, which would bring the country's official death toll from the H5N1 virus to 37.

The girl, from Pamulang on the outskirts of Jakarta, died late Thursday after apparently coming into contact with sick poultry, said Nyoman Kandun, a senior Health Ministry official.

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The girl's 10-year-old brother died Monday with similar flu-like symptoms, but no samples were taken, said Dr. Hariadi Wibisono, a senior official at the national Health Department. The boy died in an emergency room before being treated, and the family immediately took him home for burial, he said.

"The family reported that chickens died near their house, and we have been told they had contact with birds," Wibisono said.

The children's father said he was aware of bird flu, but had no idea the virus was circulating near the family's house.

"I am very shocked. I do not understand how bird flu occurred in my neighborhood," said Suryoto, who like many Indonesians uses only one name. "This internationally known disease took away my lovely children only in days, less then a week."

He said his son fell ill with a fever after playing soccer with other children near their home. When it became difficult for the boy to breathe, Suryoto rushed him to a hospital, but it was too late.

"He died before the doctor could do something for him," said Suryoto, adding that his three surviving children were healthy.

Meanwhile, Bayu Khrisnamurti, secretary-general of the National Committee of Avian Flu Control, said a mass poultry slaughter would begin soon in the North Sumatra village of Kubu Simbelang.

The village attracted international attention last month after six members of a family died of bird flu and a seventh fell ill. An eighth family member was buried before samples were collected, but WHO considers her part of the cluster of cases — the largest ever reported.

Experts have not found any link between the relatives and infected birds, which has led them to suspect human-to-human transmission. But no one outside the group of blood relatives has fallen ill and experts say the virus has not mutated.

Bird flu has killed at least 127 people worldwide since it started ravaging Asian poultry farms in late 2003. It is difficult for humans to catch, but experts fear the virus could mutate into a form more easily transmissible between humans, potentially sparking a pandemic. So far, most human cases have been linked to contact with infected birds.

Indonesia trails only Vietnam, where 42 people have died, in the number of bird flu deaths.