SAN FRANCISCO — San Francisco Bay Area health officials were trying to determine Monday if three people who died and five who were sickened after eating Thanksgiving dinner at a church event got sick there or at the assisted living facility where they all lived.

Sutter Delta Medical Center in Antioch said in a statement Monday it received eight patients with “probable food-borne symptoms” between Friday and Saturday.

Three of the patients died, four patients were treated and released, and one remained hospitalized, the hospital said.

“We do not believe there is any risk to the general public,” said Dr. Louise McNitt, deputy health officer for Contra Costa County.

It’s unclear exactly what caused the illness, she added.

All eight lived at the same assisted living facility and ate a free Thanksgiving dinner at the American Legion Hall in Antioch along with other residents and staff members who did not get sick, McNitt said.

The traditional Thanksgiving dinner of turkey, mashed potatoes, stuffing, green beans, bread and pies was served by the Golden Hills Community Church, which has held the event for several years, said Dr. Marilyn Underwood, environmental health director for Contra Costa Health Services.

Volunteers prepared the mashed potatoes, green beans and stuffing on site, at a commercial-grade facility. The rest of the meal, including the turkey, was donated by other food facilities, Underwood said.

They served 835 people who included homeless people, residents of assisted living facilities, and anyone who wanted to have a good holiday meal, she said.

McNitt said that no other reports of illness related to the dinner have been received and that officials were trying to determine if there were other people who got sick but didn’t seek medical care.

McNitt and Underwood declined to provide the name of the living facility or any details about the eight patients, citing patient privacy concerns.

Contra Costa County coroner’s officials said they could not release the names of those who died pending notification of next of kin.