The Minnesota Department of Health is investigating a report that people got sick from eating the food at a fundraiser held at a church.

The banquet took place Sunday at the Lakewood Evangelical Free Church in Baxter, Minn. The problem was reported Thursday.

The event was a benefit for New Pathways of Brainerd, a group that helps homeless families with children find safe transitional shelter.

The fundraiser was catered by Baxter’s Prairie Bay Restaurant, according to the MDH.

Investigators believe about 275 people were at the event, but it isn’t yet clear how many were exposed or how many became ill. Early signs point to a norovirus as a cause, but that has not been confirmed.