The blaze broke out around 5:35 a.m. at 119 Union St., in Catasauqua, bringing more than 100 firefighters to the scene.
Firefighters, however, were unable to get more than a few feet inside of the multi-level home due to "floor to ceiling hoarding conditions," LehighValleyLive says citing Fire Chief Rich Hertzog.
Crews made three separate attempts from three different entry points, the chief said.
The female homeowner who had initially been unaccounted for was later located and pronounced dead by Deputy Coroner Gabrielle Alcaro just after 4 p.m., LehighValleyLive reports.
The homeowner is listed on property records as Cynthia Acerra. An autopsy was expected to occur Monday, April 5.
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