Another body has been found inside the rubble of a mobile home fire in the Verde Village near Prescott, authorities in northern Arizona said.
Yavapai County Sheriff's officials said the fire broke out early Saturday and two bodies originally were found.
They announced Monday that a third body now has been discovered.
Sheriff's officials said two of the victims are 72-year-old Ernest Houck and his 71-year-old sister, Judy Huntington.
The identity of the third body is being withheld until relatives can be notified.
The county's medical examiner says the cause of death for all three victims was smoke inhalation and thermal injury.
Detectives and fire investigators are working to determine the cause of the fire.
A number of fire crews responded to the blaze. They included the Verde Valley Fire District, Cottonwood Fire Department and additional crews from the Clarkdale and Sedona Fire Districts.
Several ambulances and the rehabilitation unit from Verde Valley Ambulance responded to the scene as well.
Copyright 2013 Associated Press. All rights reserved. CBS 5 (KPHO Broadcasting Corporation) contributed to this report.