Police confiscated more than 800 pounds of the fat-burning drug clenbuterol in central Henan province and destroyed a production site and two distribution networks, Xinhua reported.
Clenbuterol is fed to pigs to stop them from accumulating fat but is banned in China because it is poisonous to people when ingested in pork.
China's state-run news agency reported Ma Weiya, a senior official with the Ministry of Public Security, said the government was initiating a one-year crackdown on illegal additives in pig feed after ham-producer Shuanghui was accused last month of using clenbuterol-tainted pork in its products.
Almost 18 tons of pig feed suspected of containing clenbuterol were confiscated during a province-wide check March 15-23 in Henan, authorities said.
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