Forest guards heard 40 rounds of AK-47 firing near Borkhupkorali camp under Burapahar range of the world heritage site after midnight, the sources said.
After a search operation, the carcass was recovered this morning and 36 empty cartridge shells and three live cartridge were found nearby.
The paramilitary Mizo Regiment and forest battalion have launched a joint operation to track the gang of poachers suspected to be involved in the attack.
This is the second rhino killed in the Park and the seventh in the state this year.
