The fish eating birds, locally called Monihori, were found dead in Barseleka beel (water body) in Bagori Range of the Park since yesterday, Range officer K K Deka told PTI today.
Deka and other KNP forest officers rejected media reports that the migratory avians had died due to an outbreak of H1N1 (Bird Flu) in the Park.
After preliminary investigations they suspected that the birds may have died here after being poisoned elsewhere during the course of their migratory journey.
The authorities asserted that if Avian Flu had broken out inside the Park then other birds, including pelicans, wild ducks and fowl would not have remained unaffected.
Samples of the dead Greater Cormorant's carcass had been sent to the Forensic Science Laboratory in Guwahati for further investigations and for establishing the cause of their death, Deka added.