Dozens of preschool children at state-run day-care centers in the Bosnian capital, Sarajevo, reportedly have become sick with symptoms associated with food poisoning.
Out of more than 90 children who have become ill, at least 30 had to be hospitalized.
Doctors said none of the children were in a life-threatening condition.
The children are suffering from fever, diarrhea, and abdominal cramps.
Health officials say such symptoms are common among people with salmonella poisoning.
Nearly 3,000 children attend 29 government-run preschools in Sarajevo.
Preschool service managers said their food is prepared in a central location in Sarajevo and distributed to the schools.
Food samples from the preschools have been taken for inspection.
In neighboring Serbia, more than 40 people have become ill and five have died during the past week due to salmonella poisoning.