An elephant weighing between 1.7 and 2.5 tonnes was found dead more than a week ago on a rubber tree in a rubber plantation in the central province of Nghe An.
At 9 a.m. on Saturday, a forest ranger discovered a decomposing elephant carcass in a stream in Thanh Chuong district.
The elephant was identified as an adult male, having lived nearly 30 years with intact tusks nearly 40cm long.
Officials from the Thanh Chuong district ranger department said the inspection ruled out the possibility that the elephant was hunted, as the tusks were not stolen.
They suspected the elephant had died of illness, old age or natural disasters, following heavy rains and recent flooding in the area.
District authorities sent a team comprising forest guards, police and soldiers to protect the area overnight.
In February, residents also discovered an old dead elephant in a natural forest in the mountainous Quy Chau district of Nghe An.
Nghe An has more than 13 wild elephants, the third largest in the country after Dak Lak and Dong Nai.