At least 30 people were sickened and two people died after eating at a restaurant in Montana.

The restaurant, Dave’s Sushi in Bozeman, MT, remains closed and health officials say there does not appear to be an ongoing threat to the public. There has not been a definitive source of the illnesses identified yet, but officials say morel mushrooms are a likely source.

Anyone who ate at the restaurant from late March through mid-April is urged to contact a doctor and public health officials, according to the Gallatin City-County Health Department and the Department of Public Health and Human Services. Contact information for all local health departments is here. 

People who became ill generally had symptom onset between 30 minutes and 4 and a half hours after eating at the restaurant. Symptoms include but are not limited to nausea, diarrhea, stomach cramps, and vomiting.

Health department officials report that the mushrooms were imported and have determined that they were not distributed to restaurants or other businesses in Montana.

“The mushrooms were cultivated in China, shipped to a distributor in California, and subsequently sent to multiple states. There are no known associated illnesses in other states identified at this time,” health department officials said.

Officials from the U.S. Centers for Disease Control and Prevention along with the U.S. Food and Drug Administration State are involved in the investigation. The investigation remains open and the restaurant will remain closed until further notice.

Of the 30 known patients, three have required hospitalization. The cities of patients have not been reported, but officials across the state are involved in the investigation.

“The manner and cause of death for two individuals will remain pending until autopsy and toxicology results are available. Preliminary investigative findings indicate that food containing morel mushrooms may be the exposure of concern. Currently, no pathogen/toxin has been identified, and both state and federal partners continue to test clinical and food samples,” according to a statement from the county health department.