A file photo shows that a snow leopard jumps in the snow-covered Xining Wildlife Park in Xining, Qinghai province, on Nov. 7, 2018. [Photo/Xinhua]

An elderly snow leopard escaped from its enclosure at the wildlife park in Xining, capital of northwest China's Qinghai Province, on Friday, and had not been located as of 5 p.m., according to the park management.

The snow leopard named "Naonao" was found missing by park staff in the early morning, leading to an immediate emergency response and closure of the park. Local departments such as emergency services, fire rescue, forestry and police have joined the search operation.

Search efforts were hindered by the park's complex terrain and dense vegetation, as well as the animal's elusive nature. Preliminary assessments indicate that the snow leopard remains within the park premises.

"Naonao" is a 16-year-old female snow leopard, equivalent to 80 in human years. Snow leopards are a first-class protected species in China.