China's Ministry of Agriculture has issued an urgent circular to local government departments ordering them to clamp down on an illegal additive used in pig-feed.
The notice comes soon after 300 people in Shanghai suffered acute food poisoning after eating pork which contained traces of the additive, which is used to produce leaner meat.
The victims were admitted to hospital with symptoms of dizziness, quickened pulse rates and muscle cramps after they ate pork, pig liver and other pig organs. Most of the patients have left hospital, while some remain for further observation.
The additive has been banned for years but is still being used illegally in some regions, the ministry said in the circular, asking local watchdogs to enhance supervision to ensure food safety and protect people's health.
The licenses of enterprises producing food products containing banned medicine should be cancelled, and inspections should be carried out in key areas, the ministry said.
The pork products in most parts of China are safe, the ministry said.