Hesheng, a captive-bred panda has died two months after it was released into the wild in southwest China’s Sichuan province, authorities said on Thursday.

The male panda, born in 2013, had undergone training at Liziping Nature Reserve from March 2016 and was released into the wild in July. It died two months after it was released in September last year, Chengdu Research Base for Giant Panda Breeding said.

On September 11, Hesheng was spotted safe and well some 3.5 km away from where he was released, the research centre said.

Just weeks later, however, on September 27, his GPS collar sent an alarm, prompting an overnight search for Hesheng.

When researchers found his limp body they noticed injuries on his right shoulder, right ear and right hind limb.

An autopsy confirmed Hesheng died of septicemia due to a bacterial infection after being attacked by unknown animals, state-run Xinhua news agency reported.

Giant pandas are among the world’s most vulnerable and rare animals, with a known population of only 1,600, mostly in China. The average lifespan of wild pandas is normally 20 years, but those in captivity usually live longer.