Dharmendra, a one-horned male rhinoceros brought to the Delhi Zoo from Assam as part of an animal-exchange programme, has tragically died an “unnatural death,” officials reported on Thursday.

The 11-year-old rhino, which arrived in September 2024, was in good health and had been paired with a female rhinoceros in the hopes of breeding.

Delhi Zoo Director Sanjeet Kumar stated, “Dharmendra was discovered dead in his enclosure early in the morning, before the zoo opened to visitors.” The animal was immediately transported to the zoo’s veterinary hospital but was pronounced dead on arrival, he added.

“Given the unnatural circumstances of the death and no prior history of illness, we are considering all possible causes and have launched an investigation,” Kumar explained.

Experts from the Indian Veterinary Research Institute (IVRI) in Bareilly have been called in for a thorough examination and postmortem. Anthrax has been ruled out, and the postmortem is scheduled for Friday. Meanwhile, the National Zoological Park’s (NZP) joint director has been tasked with conducting a detailed inquiry and submitting a report. The female rhinos, although showing no signs of abnormality, are under close observation, Kumar assured.

Dharmendra was brought to the Delhi Zoo as part of an exchange programme with the Assam Zoo. The arrangement also included the transfer of a male Bengal tiger and a pair of pied hornbills to Delhi, while Assam received a female tiger, a blackbuck, a white buck, and a pair of blue and yellow macaws in return.

After completing a mandatory quarantine, Dharmendra was introduced to the public in October 2024.

This incident comes on the heels of another tragic event at the zoo—the death of a nine-month-old white tiger cub on December 28 due to “traumatic shock and acute pneumonia.” Two other tiger cubs, born in March 2024, remain under observation at the zoo’s veterinary hospital.