An electrical problem in the area of an extension cord likely caused the city house fire Monday that killed two people and injured three firefighters trying to rescue them, an official said.

"We've located some extension cords we think are the most probable cause of the fire," Trooper Dustin Shireman, a state police fire marshal, said on Friday. "There was nothing suspicious to suggest the fire was incendiary. It was accidental."

The blaze started in the basement of the middle row home at 225 E. Madison St., he said. The ignition source is undetermined.

State police and city fire marshals will not likely ever be able to determine for sure exactly what caused the fire, Shireman said.

"The collapse of the first floor and the damage makes it difficult," he said.

The fire marshals spent three days investigating while the rubble was taken away from the site in a meticulous, top-down fashion.

They determined that an electrical cord hooked to a power strip had been used to provide electricity to a radiator-style space heater, Shireman said. It was the only form of heat in the basement.

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Bill Stone and his 13-year-old son, Dakota, were sleeping in the basement at the time of the fire, Shireman said. The space heater was on when they went to bed about four hours earlier.

The residents said they believed that one of them woke up at some point during the night and unplugged the heater, he said. It was unplugged when it was uncovered in the rubble.

Damage in the area did not show the fire starting at the space heater, Shireman said.

"It was not the cause of the fire," he said. A washer and dryer in the basement also were ruled out as possible causes.

Pauline Stone, 39, and the child she was baby-sitting, 6-year-old Leilani Roman, perished in the fire.

Three firefighters injured trying to save them are recovering.

rrobinson@lnpnews.com

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