A patrolling party of the national park found the carcass of the 17-year-old female elephant in Koirakocha nullha in Bisoi Range and retrieved it from a 20-ft deep nullha, officials said.
"We found cut mark on neck of the elephant. Its both tusks were uprooted," honorary wildlife warden Sanjukta Basa, who visited the site, said.
Subsequent postmortem also revealed that the elephant was pregnant. "We suspect that the elephant was killed three days ago and dumped into the nullha," a senior forest official said.