GUANGZHOU -- Fifty-two pupils and teachers from a primary school in south China were hospitalized with food poisoning on Wednesday.

The health bureau of Guangzhou, capital of Guangdong Province, said 50 pupils and two teachers from the school attached to Sun Yat-sen University suffered abdominal pain and vomiting from 11:00 a.m. to 7:00 p.m..

A preliminary analysis by the city's Haizhu District disease prevention and control center showed that victims suffered a bacterial food poisoning.

A bureau investigation found the food poisoning was probably caused by soya milk and red bean cakes that the sufferers ate for a break-time snack.

The food was supplied by Guangzhou Hongyi Food Co., Ltd.

A company source said the food was made at 6:00 a.m. the same day, sent to school at 8:00 a.m. and served to 1,558 pupils and teachers at the school at 9:15 a.m..

The bureau said the company had a valid health permit issued by the government, but it still ordered production to be suspended.

The condition of the pupils and teachers was described as stable and some had already been discharged from hospital. No deaths have been reported.