Health authorities in India on Saturday confirmed a fresh outbreak of deadly bird flu after thousands of chickens died, officials said.
The latest infection is the fourth outbreak of the H5N1 virus in the eastern West Bengal state in the past year, they said, adding that thousands of poultry perished in the hilly Darjeeling district.
"Several thousands of poultry dropped dead over the week in Darjeeling's Mathigarah village," West Bengal Animal Resources Development Minister Anisur Rahaman told AFP in state capital Kolkata.
"Samples of the dead poultry have tested positive," he said and added that 20,000 infected birds would be culled on Sunday.
The state authorities have already slaughtered five million poultry to control the virus during 2008 as India battled its worst bird flu outbreak.
The virus spread to 14 of the 19 districts in West Bengal, which has a population of more than 80 million. But India has still not reported any human case of the deadly H5N1 strain of the virus.
Officials in the northeast state of Assam last month killed 250,000 chickens to control the spread of the deadly infection, which had sparked fears of a human case after many people were reported sick.
The World Health Organization says the H5N1 strain has killed nearly 250 people, mostly in Southeast Asia, since 2003.