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WHARTON TOWNSHIP (KDKA) — Authorities are investigating a fatal fire that happened Sunday morning in Fayette County.

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When Bryan Fonner looked over at his neighbor’s house in Wharton Township on Sunday morning, he saw smoke and thought she was using her wood-burning stove.

But he soon realized that something was wrong.

“It wasn’t a normal fire. It was too much smoke, too heavy smoke,” Fonner said, “and then we heard a bang, and that’s when we went over to see what was going on.”

Fonner and his wife tried to help, but the smoke and heat were just too much.

“Really couldn’t get in to her, no, because it was just too much smoke, and you could actually feel the heat on the outside of the house,” Fonner said.

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It was too late for firefighters with the Farmington Volunteer Fire Department to make a rescue.

“When they arrived on scene, it was fully engulfed, and they were able to locate a victim inside the residence who was deceased,” Pennsylvania State Police Trooper Robert Broadwater said.

The victim is identified as 54-year-old Mary Campbell Spegar.

“Mary’s just a wonderful person. She’s the kind of person that would help you out in any way she could,” Fonner said. “She’s a wonderful neighbor. I just can’t say enough good things about her. She’s a great person.”

Campbell Spegar was born and raised in the Wharton Township community, and she’s very well-known and –liked. She’s also well-known in Uniontown where she worked in the Fayette County Courthouse as a public defender.

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The state police fire marshal is investigating the cause of the fire, which is not believed to be suspicious.