Firefighters were called to a house on East 2nd Street near Center Street just after midnight.
According firefighters at scene, the victim may have been a hoarder. Fire officials said there was a lot of stuff inside the home.
The home is a duplex, and it appears the fire started in the unit on the left.
Firefighters arrived at the home around 12:40 a.m. Monday and found very heavy smoke and some flames.
When they went inside, they found the female victim. Firefighters brought her outside, but sadly, she had already died.
The mother of the woman killed was at the scene. She said her daughter was just 41 years old.
Sadly, a dog was also killed in the fire, officials said.
"There was one other pet, looks like a dachshund, and it was found inside, deceased as well," Asst. Chief Phillip Arroyo said. "Pets are family too, and it was unfortunate."
As for the cause of the fire, the Deer Park Fire Marshal's Office is investigating.
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