LOUISVILLE, Ky. (AP) - Victims of a pre-dawn house fire July Fourth that killed three children and two adults apparently didn't hear a second-story smoke detector, and investigators were trying to find out what happened to another detector once installed as part of a fire safety program, a Louisville fire official said Monday.


The investigation into the holiday tragedy continued as the Jefferson County coroner's office said a 10-month-old boy became the fifth victim.

It could take weeks for investigators to determine a cause due to "the nature of the incident," Sgt. Salvador Melendez, spokesman for Louisville Fire & Rescue, said by phone Monday.

"Right now, everything is being considered," Melendez said. "So nothing is being ruled out."

Investigators found a working smoke detector on the second floor, but it apparently didn't alert at least seven people asleep in the two-story house when the fire erupted early Saturday.

"We understand that it couldn't be heard because the door to the second floor was closed, and all the occupants were on the first floor at the time of the fire," Melendez said.

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