Yet another celebrity has passed away in 2016. This time it is Pan Pan, the world's oldest male panda, who died at 31 in south-west China's Sichuan Province on Wednesday (Dec 28), Xinhua news agency reported.

An autopsy is being carried out to find the cause of his death, though the circumstances are not thought to be suspicious, according to Xinhua.

"Pan Pan was the equivalent to about 100 human years, but he had been living with cancer and his health had deteriorated in the past three days," Tan Chengbin, a keeper with the Dujiangyan base of the China Conservation and Research Center for Giant Panda, told Xinhua. "He had lost consciousness."

Today we have lost yet another one. RIP Pan Pan - He Was The Worlds Oldest Male Panda at 31. @nicolajoakley #Panda #panpan pic.twitter.com/5dGI4K3hEq — Jamie Ferguson (@JamieMirror) December 28, 2016

Though born in the wild in Sichuan's Baoxing County in 1985, Pan Pan lived in captivity from just a few months old.

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"Panda grandpa," as he became known, was diagnosed with cancer in June this year, and also suffered from common old-age conditions, such as cataracts and poor teeth, Xinhua said.

Pan Pan, which means "expectation" in Chinese, fathered many cubs over the past 20 years. He has more than 130 descendants, accounting for 25 per cent of the world's captively bred panda population.