Sixteen public health teams also began slaughtering poultry within one kilometer of the state-run farm in an attempt to halt the spread of the virus, said Jyotirmoy Chakrabarty, joint director of the state's Animal Research Department.

Chakrabarty said some poultry on the government farm were infected with the H5 strain of bird flu, and more tests were under way to determine whether it was the virulent H5N1 subtype.