Jakarta. Four of 10 sperm whales that were stranded and found by residents on the coast in Ujung Kreung, Aceh, have died, though the remaining six were released into the ocean on Tuesday (14/11).

Sapto Prabowo, head of the Natural Resources Conservation Agency (BKSDA) of Aceh, said the dead whales might be contaminated with fungal infections.

"So far, we have suspected the four dead whales, which were stranded in Aceh Besar, had fungal infections in their skin and mouths," Sapto said in Aceh Besar on Tuesday, as quoted by state-run news agency Antara.

The 10 whales were reportedly stranded on Ujung Kreung Beach on Monday morning.

Sapto said BKSDA, along with whale experts from Bali, have examined the dead whales and have come up with preliminary findings that show the whales had fungal infections that produced worms.

He said the fungus infections affected the mammals' metabolism, presumably causing the death of the four stranded whales.

However, he said an autopsy is now being conducted by a team from the faculty of veterinary medicine at Syiah Kuala University in Banda Aceh to determine the cause of death of the four whales.

"The cause of the death of these whales still remains unknown. We still need to wait for the results of the autopsy," Sapto said.

Meanwhile, Basri, head of the whale evacuation team and an official at the Ministry of Marine Affairs and Fisheries, said the four dead whales will have to be buried on Ujung Kreung Beach, as the team does not have the proper equipment to cast the whales back into the ocean.

"Usually, they are drowned in the oceans when they are dead, but due to not having the tools, they will have to be buried," Basri said.