Report reveals more details on house fire that killed 5, but source still unknown

A fire in a north Minneapolis building that killed five children in February started in an area where investigators found an unknown melted mass, according to a report released Wednesday by the state fire marshal's office.

The report provides more details about the fire, noting that it started in the northwest quadrant of a middle room on the second floor of the upper duplex where Troy Lewis lived with his eight children.

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Investigators have not yet determined what caused the fire, but a forensic electrical engineer removed the unknown mass so it could be examined by X-ray.

Lewis has said he complained to the property owner about a lack of heat in the apartment, and that he had used the oven and a space heater to compensate for its broken radiators.

Landlord Paul Bertelson, however, has said Lewis never raised any concerns about the heat.

City records show an inspector cited the property for lack of electricity in August and threatened to condemn it. The inspector also noted "additional electrical problems."

The city marked those violations as "resolved" in September.