Tan Tan, the oldest giant panda in Japan, has died at age 28 at a Kobe zoo after contributing to friendly ties with China and cheering up locals in the aftermath of a major earthquake that hit western Japan in 1995, the zoo said Monday.

The panda, who was between 80 and 100 years old in human years, came to Oji Zoo from China in 2000 for breeding purposes.

She had been scheduled to be sent back to her home country in July 2020 upon the expiration of her lease agreement, but it was delayed due to the coronavirus pandemic and later because she was undergoing treatment for cardiac disease.

Giant panda Tan Tan is pictured at Oji Zoo in Kobe, Hyogo Prefecture, western Japan, on Sept. 16, 2023, her 28th birthday. (Kyodo) ==Kyodo

The zoo reported that Tan Tan suffered cardiac arrest late on Sunday, with attempts to resuscitate her proving unsuccessful. It is believed that her death was the result of complications from heart disease, which had left her in a weakened state.

Tan Tan had been on medication since her diagnosis of age-related cardiac disease in 2021. She stayed in Japan after discussions between the zoo and Chinese officials, considering the necessity for medical treatment and the increased transportation risks given her advanced age.

The zoo praised Tan Tan for encouraging locals during recovery efforts following the 1995 Great Hanshin Earthquake, which struck Kobe and its vicinity.

The zoo had refrained from showcasing Tan Tan to the general public since spring 2022 due to her health condition. Since the fall of last year, she had been less active and sleeping longer.

Administering medication became difficult after her condition deteriorated from around the middle of last month, and she started refusing to consume liquid nutrition, the zoo said.

The zoo plans to set up a flower stand for Tan Tan on its premises starting Tuesday, with a farewell event also being considered.

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