Ten Borneo pygmy elephants were found dead over the last two weeks in Malaysia's Sabah state, official of Sabah Wildlife Department said on Tuesday (January 29).

Handout photos obtained from the department showed elephant carcasses found in the rainforest of the state on Borneo Island.

Four elephants were first reported dead last Wednesday (January 23) and another four were found dead two days later.

Director of the department, Laurentius Ambu, said the eight dead elephants were suspected to be linked with "two highly decomposed elephant carcasses" found earlier this year.

All the dead elephants were found in the Gunung Rara Forest Reserve, located in the south of the state.

A department vet said no obvious external injuries were found on the animals but they were suffering from severe haemorrhages and ulceration of the gastrointestinal tract.

"We highly suspect that it might be some form of acute poisoning from something that they had eaten but we are still waiting for the laboratory results of the chemical analysis from samples taken from the dead elephants to confirm the diagnosis," senior veterinarian Sen Nathan from the department was quoted as saying in a statement.

Seven of the dead elephants were females and three were males, ranging from four years old to around 20, the statement said.

The World Wildlife Fund (WWF) estimates there are less than 1,500 Borneo pygmy elephants found in the wild with most of of them residing in Sabah state. The elephant is smaller than other Asian elephants and their African relatives with larger ears and gentle nature.

Officials declined to make further comment as the incidents were still under investigation.

A special force including the Sabah Wildlife department, Forestry department, WWF Malaysia, police and Yayasan Sabah which sponsored part of the conservation fund for the animals has bee set up to investigate the cause of the deaths.

(VIDEO SOURCE: REUTERS)