By Subir Bhaumik
BBC News, Calcutta
Authorities in Manipur in India's north-east, have started killing all poultry in the state's capital, Imphal, after an outbreak of bird flu.
Officials are picking up poultry from markets in Manipur for killing (Pic: David Mayum)
More than 150,000 birds and backyard poultry will be killed within a week, a state official said.
The deadly H5N1 virus has been reported from a poultry farm near Imphal where 133 chickens have died in four days.
The virus can cause illness and death in humans, but scientists say the chances of being infected are very low.
Officials say the special focus is on a five-km area around the infected poultry farm at Chingmeirong, near Imphal, from where the outbreak of avian influenza has been reported.
Director of the animal husbandry department in Manipur, Th Dorendra, said the samples were sent to the federal testing laboratory in the central Indian city of Bhopal - the High Security Animal Disease Testing Laboratory.
"We have the report from Bhopal and that's real bad news for us," Mr Dorendra said.
The authorities have formed 40 medical teams, each with 34 health department employees, to do a house-to-house surveillance in a 10-km area around the infected farm.
Mr Dorendra said 80,000 households, with half a million population, will be covered.
Many poultry farms in India give bird flu vaccines to their chickens
"We will look out for people with breathing trouble, even cough and cold and anyone with the symptoms will be subjected to rigorous medical examination," he said.
Consumption of chicken and ducks has dropped in Imphal and other area of Manipur after samples were sent for testing to the federal laboratory in Bhopal last week.
The farm workers and the veterinary department employees who conducted the checks there were taking Tamiflu, the most popular drug for treating bird flu, as a precautionary measure.
Health workers involved in containing the infection in the area will also be given Tamiflu, Th Dorendra said.
India, which declared itself free of bird flu last August after two outbreaks in western states, has not reported any infections in its multi-billion-dollar poultry industry or among backyard poultry this year.
Experts say they suspect the disease has come into Manipur possibly from neighbouring Burma.
Manipur chief secretary, Jarnail Singh, said border guards have been ordered to stop people from bringing in poultry illegally from Bangladesh, China and Burma.
All the three countries - which neighbour India's northeast - have reported bird flu this year, with China also reporting human cases and deaths due to the H5N1 strain.
Globally, the H5N1 virus has killed nearly 200 people out of more than 300 known cases of human fatalities due to avian influenza, says the World Health Organisation.
Also, hundreds of millions of birds have died from the infection or have been slaughtered.