The fire broke out shortly before 10:00 a.m. in the 1500 block of Roosevelt Drive.
The view from Chopper 6 HD showed heavy flames pouring out of one of the homes.
Firefighters began battling the stubborn fire that quickly went to three alarms.
The owner of the home at the center of the fire, John Morgan, said an electric space heater ignited bed linens.
"We jumped up and got out of the room," said Morgan. One of his three dogs perished in the fire and he suffered a minor burn.
About 25 trucks and crews, including neighboring companies were called to the scene to fight the flames.
Two Darby firefighters suffered minor burns to the backs of their necks from falling debris.
One couple whose lived in one of the homes for 30 years came home to find their house in a smoky ruin.
The wife was speechless and her husband, Alan McCall says "we pulled up to our home and heard the volunteer fire department calling for alarms and we saw smoke pouring out."
The American Red Cross said it was helping five displaced families, a total of 11 people.