The Duke and Duchess of Cambridge were "angry" to hear that poachers slaughtered a rhino at Kaziranga National Park, just hours after their visit to the highlight the plight of endangered species.
Footage obtained by ITV News shows the adult greater one-horned rhino covered in blood and with its horn hacked off at the World Heritage Site.
The latest death means the royal visit to the park was bookended by illegal rhino slaughter, as a female rhino was shot dead for its horns just two days before they arrived.
A spokesman for Kensington Palace said:
Warning: Contains distressing imagery of the rhino killed on Wednesday
Prince William was said to be "appalled" by the poaching that happened shortly before the couple's visit and has vowed to help tackle poaching.
On Wednesday evening, while the couple were en route to the next leg of their tour in Bhutan, gunmen using AK47s shot dead the adult rhino before removing its horns.
Rangers discovered the mutilated animal inside the Burapahar forest range of the park, located in Assam, with 88 empty shell cases surrounding it.
The rhino was killed 30 kilometres from the jungle resort where William and Kate were staying during their official visit to the park.
Poachers feed a mistaken belief among some people across Asia that ground-up Indian rhino horn is a cure for ailments from impotence to rheumatism.
They can reportedly earn up to £212,000 a kilogram for the substance and rangers struggle to fend off criminal gangs who have powerful weapons and plenty of ammunition.
Despite its latest instances of rhino poaching, Kaziranga park is deemed a conservation success - but it is battling criticism of its controversial "shoot-to-kill" policy regarding poachers.
Conservation charity Save the Rhino has told ITV News it is dismayed to hear of the latest rhino slaughter, but its director Cathy Dean defended the Park's right to allow guards to engage in armed contact with poaching gangs.
The charity believes rangers should look to capture, rather than kill poachers where possible, but says those looking after endangered animals need better equipment and training.
Kensington Palace told ITV News that the Duke of Cambridge is planning to fund training and equipment for rangers, through his charity United for Wildlife.
In 2015 Kaziranga lost 20 rhinos to gun-toting poachers.
The latest killing takes the number of one-horned rhinoceros shot dead at the park to seven this year.
"Rangers need better equipment and proper weapons training," said Dean. "We'd like this to become a top priority."