Sioux City Fire Rescue is identifying the two men rescued from a fire on W. 15th St. Sunday night.
The victims are 64-year-old Franklin Barclay and 60-year-old Darrold Barclay.
The Barclays are brothers and were the only occupants in the home at the time of the fire.
Both men are still at Saint Elizabeth Hospital in Lincoln, Neb.
Their conditions have been upgraded to "stable."
The investigation into the cause of this fire revealed a lit cigarette ignited a mattress in the upstairs bedroom.
The fire then spread throughout the contents of the bedroom.