SHENZHEN - Classes have been suspended after 140 students were sickened by norovirus at a school in south China's Guangdong Province, local authorities said on Wednesday.

Grade I and II students of Shenzhen Baihe Foreign Language School began showing signs of food poisoning after experiencing stomach aches and vomiting on Monday afternoon. By Tuesday morning, a total of 140 students out of the school's 1,400, showed similar symptoms.

An investigation by the local disease prevention and control center showed the mass vomiting was caused by the noro virus infection. The affected students were taken home by their parents for treatment.

The school will strengthen disinfection in public areas and ask staff to wash their hands frequently. Classes for Grade I and II were suspended.

Symptoms of the highly-contagious stomach virus include vomiting, diarrhea, fever and body aches. Usually patients recover within several days.