More than 950 schoolchildren have fallen ill at nine schools on Japan's northern Hokkaido island in a suspected outbreak of food poisoning.
Thirteen children are in hospital in the city of Iwamizawa; 48 teachers and other school staff also have symptoms.
The affected schools will remain closed until the end of the week.
The outbreak was so widespread because, like many cities in Japan, Iwamizawa operates large central kitchens which deliver food each day to many schools.
Three of these kitchens have been shut as well while an investigation is carried out.
The children began to fall ill last week after eating lunch of miso soup, salad and Japanese radish with minced meat.
In all, 953 students have been affected but none is in a critical condition.
After earlier incidents of food poisoning, schools in Japan are required to keep samples of all meals served over the previous seven days.
They are being tested to determine the cause of the outbreak but the health authorities suspect salmonella may be to blame.