With close to two lakh birds culled in the northeast State of Manipur, fingers are now being pointed to Myanmar from where the affected birds may have entered India through the 1600-km long porous border.
The Centre has already alerted neighbouring Mizoram to check illegal smuggling of hens from across Myanmar where incidents of bird flu outbreak have been more often.
Manipur along with Mizoram, Nagaland and Arunachal Pradesh share border with Myanmar.
"Government of India has issued an advisory to the northeast States to restrain from imposing any restriction on the Inter-State movement of poultry and poultry product and intensify surveillance especially vigilance on the border with the countries that have reported outbreak of avian influenza," a release from the ministry of Agriculture stated.
A day before India confirmed the outbreak of bird flu on July 25 after samples sent by Chingmeirong Ira poultry farm in Manipur's East Imphal district tested positive, there were reports of its outbreak in south Myanmar.
There were also reports of bird flu outbreak in Myanmar during February, April and June this year, and the latest outbreak is reported as recent as Monday in southeast Myanmar.
Meanwhile, the Centre today said confirmed the culling of 1.85 lakhs of poultry birds with operations of control and containment operations continuing on Tuesday.
Culling and disposal will cover all 86 sectors in the 0 to 5 kms zone followed by mopping, clean up and disinfections, the government release stated.
The government has also refuted the reports of 'unusual' deaths of birds from East and West Imphal districts of Manipur or in any part of the country.