Investigating officer Akhilesh Pratap Singh told CNN that the dolphin’s carcass was found on December 31 on the banks of the Sharda Canal in the Pratapgarh district.
On Thursday, three individuals allegedly seen in the video were arrested, police said. Nine people – who can also be seen in the video – are currently still on the run, according to Singh.
The video shows a group of men killing the dolphin with sticks and an ax. Some laughed as the dolphin’s almost lifeless body was dragged around by its fin in the shallow water.
Forest official Varun Singh, who was part of the initial investigation, told CNN the dolphin was an adult Ganges river dolphin.
The Ganges River dolphin was “once in tens of thousands of numbers”, but has declined “once” in tens of thousands of numbers over the past century, according to the World Wildlife Fund (WWF).
The rare freshwater dolphin is essentially blind and, according to the WWF, is known locally as ‘susu’, a reference to the sound it makes when it breathes.
When hunting, the dolphin makes ultrasonic sounds that repel fish and other prey that enable them to visualize an image in their mind.
According to the WWF, female dolphins in the Ganges River give birth to only one calf once every two to three years.