KOLKATA, Jan 28 India's West Bengal state said on Monday that it was slaughtering chickens on a “war footing” as bird flu spread to new areas of the highly-populated province of 80 million people.

The disease has now been found in 13 of 19 districts in the eastern state, prompting fears it may reach local capital Kolkata which has a population of 13.5 million people.

The local government said it could revise the target number of birds to be culled up to three million, of some 20 million fowl counted in the state.

“We are worried the H5N1 virus was confirmed in samples from villages just 22 kilometres from Kolkata,” West Bengal animal resources development minister Anisur Rahaman said.“If it is required, culling teams will work throughout the night.” More than 1.5 million birds have been culled since the outbreak was reported a fortnight ago.—AFP