MILROY, Ind. (AP) -- A friend of the woman who rented the apartment where a fire this week killed three young boys said the building had long been having electrical problems.
It was an overloaded electrical outlet that investigators on Thursday ruled sparked the blaze that left another child critically burned.
''It appears there were several small appliances plugged into it along with at least one space heater,'' said Pam Bright, a spokeswoman for the state fire marshal's office.
A woman who lived in the apartment also remained hospitalized from the fire early Wednesday. Two other children and a man who also were at the apartment have since been released from the hospital.
The fire gutted the top floor of the two-story brick building and burned off the back half of the roof. The Our Place Pizza Parlor below was damaged, but investigators did not believe anything there caused the fire.
''They are really confident that the fire started up in the upstairs apartment,'' Bright said.
Chuck Dyer, a friend of apartment resident Bridget Quinlan said the building's electrical system had seemed inadequate.
''Every time one of the space heaters would kick on, it would dim the lights down,'' he said.
The three children presumed killed were Bridget Quinlan's son, Christian Rankin, 2, and his cousins, Jacob Quinlan, 6, and Josh Quinlan, 2. Jacob and Josh are the sons of Bridget Quinlan's sister Nicole, who was not at the apartment at the time of the fire.
Bridget Quinlan, 27, and other adults rescued both of the children of Stephanie Quinlan, who is also Bridget Quinlan's sister. She was in Florida at the time of the fire, while her boyfriend, Russell Messer, 23, was in the apartment when the fire started, said Shawn Longerich, of the People's Burn Foundation of Indianapolis, a group that assists fire victims.
Bridget Quinlan was released from a hospital on Thursday, while her other son, Zachary Ian Rankin, 3, remained in critical condition at Riley Hospital for Children in Indianapolis.
Despite the severe damage inside the apartment, investigators were able to determine that a space heater was plugged into the same outlet as a television set, a DVD player and a lamp, overloading the outlet.
''In that older building, it is an older-style circuit breaker so it didn't click off,'' Bright said.
Investigators are not certain whether the apartment had any working smoke detectors, she said.
''Granted, they might have lost of a lot of their stuff,'' Bright said. ''But if they had an alarm that had gone off, it might have given them enough extra minutes to save those other kids.''