Forest officials said that the elephant had been ill for some time and died this morning, but before the forest employees could reach the spot, unidentified people hacked the trunk and carcass.
A search operation has been launched for the perpetrators, they said.
Yesterday, an elephant with its tusks missing and a part of its trunk severed was found in a mud pit in Goalpara district which Forest minister Rockybul Hussain said was not a case of poaching but the result of a fight with another elephant.
Aaranyak, a society for biodiversity conservation in NE India, expressed concern over the death of the elephant in Dulung and injury of the elephant in Goalpara.
