A south China tiger at Shanghai zoo. Photograph: Aly Song/Reuters

A keeper at a zoo in Shanghai has been mauled to death by a rare south

In a brief statement on its Twitter-like microblog, the zoo said investigators were looking into the cause of the incident, but offered no other details.

State media reports identified the victim as a 56-year-old man surnamed Zhou. They cited unidentified colleagues as saying the man entered the tiger enclosure to clean and "did not come out again".

The animal involved was identified as a highly endangered south China tiger, considered effectively extinct in the wild after decades of being hunted as a pest.

Built on a former golf course, Shanghai zoo is one of China's largest and most popular urban animal parks.