Nearly 100 hammerhead sharks, an endangered species also known as sphyrna lewinis, were recently sold for low price in Sanya, China's southern Hainan province.

Local official explained that it is a bycatch as local the fishermen did not know they are protected species.

Duan Deyu, deputy director of Sanya Ocean and Fisheries Bureau (SOFB), said that a total of about 600 kilograms of hammerhead sharks were found, and further investigation will be conducted on fishing and trade details. He added that punishment will be imposed on those accountable.

The sharks were accidentally caught by local fishermen, according to an anonymous official with SOFB, who said the fishermen did not realize the seriousness of the mistakes they made.

Duan also explained that the sharks are not rare in the South China Sea and most local fishermen don't know they are now protected species.

Chen Shang, a researcher with the First Institute of Oceanography of State Oceanic Administration told thepaper.cn that concerned departments should strengthen publicity, and tell local fishermen how to identify protected species and free those creatures they capture accidentally.

He added that trades of those species must be strictly forbidden.

Duan pledged that they will make more efforts in this regard and improve the public’s awareness to protect ocean creatures.

The proposal to include hammerhead sharks in Appendix II of the Convention on International Trade Species of Wild Fauna and Flora (CITES), an international treaty drawn up in 1973 to protect wildlife against over-exploitation, took effect in 2014. China is one of the signatories.