Another five elephant carcasses have been discovered downstream from a waterfall where the bodies of six others were found on the weekend.
They were spotted by a drone being used to investigate the deaths of the other elephants at 656ft Hell’s Fall in Khao Yai National Park, northeastern Thailand.
The elephants are believed to have plunged to their deaths while trying to rescue a baby elephant who had fallen in.
Hell’s Fall has been notorious among locals since a herd fell to their deaths in 1992.
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Harrowing drone footage taken downstream from Hell’s Fall in Khao Yai National Park revealed five more members of the elephant family which had died over the weekend
An elephant lies across rocks downstream, surrounded by rushing torrents of water, in this drone shot taken by Thai investigators
The elephants are believed to have followed as they tried to save a calf that had fallen in ahead of them
Wildlife officials sent small drones into the area to investigate because the terrain is too rough for hiking, Nattapong Sirichanam, governor of Nakhorn Nayok province adjacent to the mountains, told reporters on Tuesday.
‘We flew drones at a height of 15 metres above the ground as we can’t walk in to confirm the deaths,’ Nattapong said.
Analysis of the footage identified the bodies of five more elephants in addition to the six originally reported after the accident.
‘We assume that there were 13 elephants in this herd and two of them survived. We are 100% confident that two of them are alive as the officials saw them going out for food around the area of Haew Narok falls,’ Nattapong said.
Officials were initially called at 3am on Saturday when a group of elephants was blocking a road by the waterfall.
The bodies of the elephants that fell grouped up a small way away from the base of the waterfall on Saturday
A group of elephant carcasses discovered by Thai officials today trapped in a corner between sheer cliff faces – the death toll now stands at 11
An elephant discovered downstream today, left, and another, right, at the rocky edge of the river
Three hours later the body of a three-and-a-half year old calf was found at the base of the falls.
Shortly after this, another five bodies were found nearby.
Two other elephants who were stuck on a ledge and extremely distressed were rescued.
Edwin Wiek, founder of Wildlife Friends Foundation Thailand, said any elephants left in the herd would have difficulty surviving as the animals rely on each other for protection and finding food.
‘It’s like losing half your family,’ Mr Wiek told the BBC.
‘There’s nothing you can do, it’s nature unfortunately,’ he said.
An elephant is submerged beneath the churning waters at the bottom of the waterfall on Saturday
Two elephants were seen to be stuck on a ledge near to the waterfall and were thrown food by the officials to help them climb back up
Two elephants that were stuck on a ledge were rescued but were said to be extremely distressed
Around 7,000 Asian elephants remain in Thailand, but around half of those living in captivity.
The death toll of 11 is the highest number of elephants to die in a single incident in Khao Yai.
The elephant population at the park is estimated to be about 300.