Logan was taken to Ogden Regional Medical Center, where she died. The Buick's driver, 67-year-old Bert R. Noorda, remained hospitalized Saturday in stable condition.
The patient in the ambulance was also treated and released.
"We were told that she received further injuries from the crash, but she has been released from the hospital so those injuries from both crashes must not have been as substantial as we previously thought," Edwards said.
Three people from the stopped cars were treated at McKay-Dee Hospital and released, Edwards said.
The driver of the ambulance wasn't hurt, but three other emergency medical responders were also treated at McKay-Dee and Ogden Regional and released.
It wasn't immediately clear how fast the ambulance was going at the time of the crash, but the speed limit in the area is 50 mph, Edwards said. Utah law requires motorists to yield to emergency vehicles but also requires emergency drivers to slow down as they approach stop signs or intersections.
"I think this one could take a while," Edwards said about the investigation. "There are a lot of factors here, a lot of different things that need to be investigated."