HILO, Hawaii — Hawaii Island police say a California man, his son and grandson were among the five people killed in a head-on collision this week.

Police say an autopsy conducted Thursday indicated 73-year-old David Ingoglia of Sacramento suffered a medical condition. Police believe this caused him to lose control of the Nissan sedan he was driving, cross the centerline and crash head-on into a Ford pickup truck.

Ingoglia died, along with his son and grandson from Costa Rica, 39 year-old son Philip Ingoglia and 9-year-old Isidora Ingoglia.

The grandfather and son died at the scene Wednesday near Pahala. The nine-year-old was died after being taken to Kona Community Hospital.

The two occupants of the truck haven't been identified. The truck overturned and caught fire after it was hit by the sedan.

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