More than 40 students from the No.4 Middle School of Tongzi County in southwest China's Guizhou Province suffered after a food poisoning incident yesterday, sources from the county education bureau announced the same day.

Preliminary diagnoses by the local health department indicated they had eaten contaminated food and were receiving treatment in hospital, said the sources.

"Students were vomiting and falling sick one after another after they attended the flag-raising ceremony this morning," said Yang Chaojian, principal of the school.

The school authorities contacted the sanitation and epidemic prevention department and rushed the sick students to a local hospital. More than 90 were receiving treatment and over 40 have developed evident symptoms of food poisoning.

The department said tainted polished glutinous rice was believed to be the cause of the poisoning, and the school has closed all five of its breakfast cafeterias.

(Xinhua News Agency June 28, 2005)