The Director General of Crisis Management of the Governorate said relief and volunteer forces are monitoring the area to prevent another fire.
Alireza Nikrooz said the fire started on Monday from a nearby village and spread to the mountainous protected area.
He added the strong winds and inaccessibility of the tough terrain were the main reasons the fire spread.
Rescue teams were deployed immediately after the incident and the crisis management helicopters sprinkled water in over 10 sorties to stop the spread of the fire.
Eight people were injured during the operation to contain the fire and were rushed to a medical center for treatment.
Nikrooz said the extent of the damage will be announced after an expert review.
Khaeez, one of the seven protected areas in Kohgiluyeh and Boyar Ahmad province, covers an area of 33,235 hectares. However, as the Maroon Dam that supplies water to Khaeez has dried up, the protected area is prone to bushfires during the scorching summer days.