Five more wild elephants have been found dead at the bottom of a steep waterfall in Thailand's Khao Yai National Park, bringing the total to 11, authorities said Tuesday.
Officials of the Department of National Parks, Wildlife and Plant said six were found dead at Haew Narok Waterfall over the weekend and the other five Tuesday.
All of them are believed to be from the same 13-member herd, of which two survivors -- a mother and her calf -- have moved to safety in the forest.
Drones were used to search for the dead elephants, with their carcasses found at different levels of the 150-meter waterfall.
Park officials and volunteers are trying to retrieve the bodies to prevent water contamination downstream.
It marks the greatest known single loss of wild elephants in Thailand. In 1992, eight elephants were found dead at the same waterfall.
Local media reported that almost every year, one or two elephants -- from among the park's population of about 300 -- plunges to death from the top of the waterfall.