Residents in the southern province of Dong Nai on Sunday found the carcass of an elephant in Vinh Cuu Nature Reserve, the eighth elephant found dead in the reserve since June 2009.
The decayed elephant weighs an estimated 300 kilograms and may have died several months ago, said Tran Van Mui, director of the Vinh Cuu Relics and Nature Reserve.
Local authorities are still investigating the cause of the death.
Meanwhile, Mui said the elephant may have been poisoned after eating insecticide-contaminated fruit from local residents' orchards.
No official conclusions about what caused the deaths of the seven other elephants have been made.