A male elephant, previously known for his "gentle temperament", has stomped a zookeeper to death during a terrifying incident witnessed by shocked tourists.
The 56-year-old Asian elephant, known as Ai A, launched the attack while preparing for a circus-style show at Changsha Ecological Zoo in China.
Tourists waiting to see the performance filmed the incident which tragically led to the death of the worker, known by his surname, Bu.
The footage shows Ai A dragging the lifeless man across the ground as onlookers yell that Bu is "gone".
Experts from the zoo suspect that the elephant's erratic behaviour was caused by the fact it was in "musth" at the time, the Daily Mail reports.
The state of "musth" is when male elephants' testosterone levels surge and they become more aggressive and are gripped by an overpowering desire to mate.
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Five other zookeepers tried to settle the animal before Bu was rushed to hospital, where he was pronounced dead.
The elephant is now being segregated from other animals at the zoo and it is understood that police have begun an investigation into the disturbing incident.
The Changsha Ecological Zoo was opened in 2010 and trains elephants to perform stunts for paying guests, including swinging hula hoops and giving massages,