An elephant collapsed and died of exhaustion while carrying tourists to the famous Angkor Wat temple in Cambodia in searing 40C heat.
Harrowing images of the elephant lying at the side of the road have been shared online and animal campaigners are calling for the end of cruel rides.
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Oan Kiri, a manager at Angkor Elephant Company, told AFP news agency the elephant had collapsed after working for 45 minutes and walking 1.2 miles.
He said: "Veterinarians concluded that the elephant's death was caused by the hot temperatures which caused stress, shock, high blood pressure and a heart attack."
The Daily Telegraph reports that the Cambodia tour operator said it was "regretful and felt pity" and would now let the 13 remaining elephants work fewer hours until temperatures drop.
However, animal rights groups say rides should not be occurring at all, explaining that the animals undergo brutal treatment while they are being 'broken in' and are often overworked.
The Metro reports that Jack Highwood, who runs Elephant Valley Project, said: "Conditions should be regulated if working Cambodia's last remaining elephants is what Cambodia actually wants to do."
A petition on Change.org calling on Cambodian authorities to end elephant rides at Angkor has now gathered thousands of signatures.
The petition reads: "The recent death of Sambo, a female elephant used for tourist rides, at the Angkor temples should be the final wake-up call for the community and tourism industry to take the steps needed to end this horrific practice.
"There is no such thing as cruelty-free elephant rides. Tourists may think that riding an elephant on holiday does not cause harm - you often can't see the cruelty - it's hidden from view. What you don't realise is that a 'once in a lifetime' or 'bucket list' item for you, means a lifetime of misery for wild animals."
The World Animal Protection (WAP) organisation recently said that elephant rides were one of the "cruellest wildlife entertainment activities" in the world.
WAP director of wildlife Kate Nustedt warned how thousands of tourists are visiting attractions unaware of the abuse wild animals are subjected to behind the scenes.
According to the Express, she said: "We need to stop the demand for elephant rides and shows, hugs and selfies with tigers and lions by exposing the hidden suffering behind wildlife attractions," she warned.
"If you can ride it, hug it or have a selfie with a wild animal, then you can be sure it is cruel. Vote with your feet and don't go."