NANNING - Police in South China's Guangxi Zhuang autonomous region are hunting the killer of a whale shark after detaining two other people for purchasing the butchered state-protected animal.

A netizen posted photos Saturday showing a shark being pulled out of the sea off Beihai city and transported away, prompting police investigations.

A spokesperson with Beihai's public security bureau said that a suspect surnamed Liao bought the 370-kg shark for two yuan ($0.3) per kg Saturday and sold it to another surnamed Huang for five yuan per kg.

Huang is alleged to have turned the meat into fertilizer and sold it on.

Whale shark is considered "vulnerable" by the International Union for Conservation of Nature and is a Class-B protected species in China. They are spotted in waters off the Guangxi and Guangdong regions every May and June.