The hornbill's video was shared on Twitter by People for Animals in India.
An endangered Great Indian Hornbill was seen being beaten with sticks with a man stamping on its neck, in an extremely distressing video from Nagaland. Three accused have been arrested in connection with the bird's killing reported from the state's Wokha district, an animal welfare organisation said.
The video, shared on Twitter by People for Animals in India, showed a man assaulting the bird with a bamboo log while too others held it in position by its wings.
Warning: The following video may be disturbing for some viewers
The bird dropped on the ground and did not make any attempt to save itself, while several others looked on. Soon after, one of the men stamped on its neck and held it by its beak. The bird looked lifeless as they let it off after the gruesome assault.
"After PFA's intervention, the Chief Wildlife Warden Mr. Vedpal Singh arrested the three accused under the Wildlife and Arms Act. They will not be released on bail," the organisation said.
The video of the incident triggered widespread anger on social media with calls for strong action against those accused.
"I'm deeply saddened and horrified about the brutality committed by a group of people against a Great Indian Hornbill that was tortured and killed in Nagaland. It is concerning to see how people commit such acts against animals instead of working toward caring for and protecting them," said Meghalaya minister James K Sangma.
The Great Indian Hornbill is an endangered species found in the Indian subcontinent and Southeast Asia. It is listed as vulnerable on the International Union for Conservation of Nature (IUCN) red list.