Casillas said he and Firefighter Crispin Nuñez ran into the residence and found the woman in her bedroom. She was not breathing when they pulled her out of the house.
Casillas said firefighters started cardiopulmonary resuscitation and by the time the woman reached El Centro Regional Medical Center she had a pulse.
Nuñez, whose helmet melted, suffered minor burns to his face. He and Casillas were taken to the hospital to be checked for burns and exhaustion. Both returned to the fire after they were checked.
The boy suffered smoke inhalation, was taken to the hospital and later released.
Casillas said it took 13 firefighters about 30 minutes to extinguish the blaze. He said the home was heavily damaged by the fire and made uninhabitable.
Casillas said the house was built in the 1940s and based on the way it was constructed, "it went up like a match."
An initial investigation revealed the fire started at several points outside the residence, leading fire crews and police to suspect the blaze was arson.
"We have ruled out all accidental causes," he said, adding the probe was ongoing this morning.
Casillas said the boy told investigators he was asleep when the fire started. The boy reported he heard popping noises and thought someone was trying to break into the house. When he saw flames, he told his great-grandmother, who then told him to call for help.
The boy told investigators he was able to escape through his bedroom window.
Casillas said the woman was in critical condition this morning in the El Centro hospital.
Fire officials estimated the damage to the house and its contents at $100,000. They added a pet rabbit died in the blaze.
The second fire erupted before 5:45 p.m. at a residential unit in Valley Mobile Home Park, 1555 Adams Ave.
It took 18 firefighters from the El Centro department about 15 minutes to extinguish that blaze. The unit was destroyed, and a husband and wife and at least one child were displaced by the blaze. The identity of the family was unavailable this morning.
The American Red Cross was on scene to offer assistance to the family.
Fire officials said the blaze was caused by faulty wiring and because a cord stretching from an outlet to a ceiling fan had become "broken down" from a mattress pushed up against the cord.
A fire official said the wife saw the flames and called the husband, who attempted to douse the fire. When he was unable to do so, they evacuated the residence and called the Fire Department.
There were no injuries in that fire, which caused about $80,000 in damage to the structure and the contents of the unit.
>> Staff Writer Darren Simon can be reached at 337-4082.