HARBIN - More than 40 students have been hospitalized after showing symptoms of vomiting and diarrhea in Northeast China's Heilongjiang province, local authorities said Wednesday.

(Screenshot from a video of CCTV News)

The ailing students are from four different elementary and middle schools in the Hulan District of Harbin, the provincial capital.

Over 200 other students with similar but mild symptoms have been kept under home observation.

Lunch samples from the four schools have been sent to the local disease prevention and control center for examination.