The smoke detector that alerted the people inside the house at 1103 10th Ave. S.W. had been installed by firefighters during a recent smoke detector blitz, according to Lenny Sanders, assistant Fort Dodge fire chief. It was apparently installed in October 2015.

As a result, nobody in the home, including three children, was hurt, and everyone got out safely.

Fort Dodge Fire Capt. Steve Teske said the fire was started by a burnt-out furnace.

While investigating the fire Tuesday, Teske said firefighters discovered a burnt cord from a power strip that had been plugged in to an extension cord.

That didn’t contribute to Tuesday’s fire, but Teske said it likely had been the cause of a previous fire.

Teske said connecting a power strip to an extension cord is dangerous, because it can overload the circuit.

“That’s really taxing the system,” he said, adding one of the people who was living in the home admitted that it was hooked up to a space heater.

Firefighters cut the cord to prevent further damage.

The American Red Cross was also contacted to help the people inside the home.