Fourteen people in southern China have been poisoned after eating pig organs suspected of containing an animal-feed additive, state media said Thursday, the second such outbreak this month.

The 14 fell sick after eating pig's liver at a dinner party in Guangzhou, in southern Guangdong province, the official Xinhua News Agency said.

They were all hospitalized with stomachaches, diarrhea, vomiting and headaches, it said.

A doctor at the hospital did not give a reason for the poisoning, but said that it could be from clenbuterol, a chemical used to prevent pigs from accumulating fat, Xinhua said.

Earlier this month, more than 70 people became sick after eating pig organs contaminated by the same chemical in Guangzhou.

China has banned its use as a pig feed additive. In 2006, more than 300 people in Shanghai were hospitalized after eating pork and pig organs tainted with clenbuterol.

The government has taken samples of the food and is investigating the cause, it said.

Earlier this week, the government vowed to widen a national campaign launched last December to stamp out the practice of adding illegal additives to food supply, after the industrial chemical melamine was found in milk products that sickened thousands of children.