BANDA ACEH, Indonesia — A Sumatran elephant has been found dead in Indonesia's Aceh province with its tusks cut off, raising suspicion it was killed by poachers.

Genman Sefti Hasibuan, head of the local Conservation and Natural Resources Agency said the carcass of the estimated 25-year-old male elephant was discovered Monday inside a palm oil plantation in Karang Hampa village in West Aceh District.

It was reported to have been rotten and missing its tusks, Hasibuan said Tuesday. Villagers estimated it died four to five days earlier from gunshot wounds.

It was the first elephant death in Aceh this year, Hasibuan said, adding that a team has been sent to the area for investigation.

The International Union for Conservation of Nature listed the animals as "critically endangered" after their numbers dropped to between 2,400 and 2,800 from an estimated 5,000 in 1985.

Environmentalists say the elephants could be extinct within three decades unless they are protected.

Sumatra's elephants sometimes venture into populated areas searching for food due to destruction of their habitat. Some are shot or poisoned with cyanide-laced fruit, while others are killed by poachers for their ivory.

In February, police in Riau province arrested eight members of a poaching syndicate and confiscated tusks worth more than $30,000, following the arrest of a local tusks buyer. The group admitted to have killed at least six elephants in Riau and neighboring Jambi provinces.