Pan Pan, the world's oldest male panda, died age 31 in Sichuan province at 4:35 am on Wednesday.

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

"Pan Pan was equivalent to about 100 human years, but he had been living with cancer and his health had deteriorated in the past three days," said Tan Chengbin, a keeper at the Dujiangyan base of the China Conservation and Research Center for the Giant Panda. "He lost consciousness and did not recover."