About 440 people now say they became ill after eating at Chipotle Mexican Grill in Kent.

Kent Health Commissioner John Ferlito suspects the cause of the illness is a norovirus.

Officials have sent stool and food samples to the Ohio Department of Health to determine the cause. Test results might be available this week.

The symptoms of norovirus typically include nausea, vomiting and diarrhea. Three people were hospitalized for one night because of severe symptoms.

The restaurant reopened Saturday, following a voluntary shutdown Friday. Workers replaced food and sanitized equipment with a bleach solution.

A Chipotle spokesman says there's no proof food was to blame and that the restaurant is working with the health department.