A total of 276 people had sought medical treatments as of Wednesday night for slight food poisoning in north China's Shanxi Province.
The patients, all employees of an automobile manufacturing company in Yuncheng City, showed symptoms of nausea and vomiting, said a spokesman with the city's government.
Most of the employees reportedly had improved after treatment, with no serious cases reported, the spokesman said.
An initial investigation indicated that the food poisoning was caused by a lunch dish of hyacinth beans and meat, he said.