PHOENIX -- A Valley family owes their lives to a stranger who woke them up after their home caught fire early Wednesday morning.
A man who was on his way to work shortly before 5 a.m. spotted smoke in the neighborhood northwest of Cave Creek and Bell roads.
That man knocked on the door hustled the family and their dog to safety.
"Arriving on scene, we saw heavy flames and smoke showing from the house, about 20 feet in the air" said Capt. Ken Kohler of the Phoenix Fire Department.
Crews believe the fire started in the laundry room and then spread to the carport and attic.
The family did have working smoke detectors in the home, but the man who knocked on their door bought them extra time to escape.
"The smoke detectors were going off when we went in," Kohler said. "But they did alert us [that] what woke them up was the passer-by knocking on the door."
While the damage to the home is extensive enough to make it unlivable, no injuries were reported.
"Possessions can always be replaced," Kohler said. "But a working smoke detector saves lives."
It's not known what sparked the fire, but firefighters say it's a good reminder for people to check their heaters and examine holiday lights.