NEWBERG, Ore. – A woman was found dead in a house fire in Newberg Tuesday morning.

Fire investigators determined that an unattended portable cook device in an upstairs bathroom caused the fire.

Newberg police said the woman, later identified as 63-year-old Kathryn Singler, was dead before the fire started and died of natural causes.

Firefighters were called to the home in the 1900 block of Paradise Drive just before 10 a.m., according to Tualatin Valley Fire and Rescue. The 911 caller reported smoke coming from the home and said no one responded to knocks at the door.

Firefighters arrived to find flames coming from the second floor of the house. Crews found the Singler's body upstairs, a TVF&R spokesperson said.

“Its always very difficult to come across something like this,” said Kim Haughn of TVF&R.

Singler's dog escaped the fire.

Efforts to fight the fire were slowed by "a significant amount of debris and clutter in the home."

Neighbors asked police to check on Singler a couple of weeks ago.

“This person doesn’t come out of the house much and so their neighbors tend to call and roughly about once a year we end up doing a welfare check,” said Captain Jeff Kosmicki with the Newberg Police Department.

He said an officer did contact Singler and she said she was OK.

Rachel Amador grew up across the street.

“Pretty sad,” she said.

She remembers Singler gardening in her yard, tending to the new plants she put in each year. But recently, she said Singler mostly stayed inside.

“She used to walk around a lot. But these past two years she didn’t really go out. She was really reclusive,” she said.

KGW's Pat Dooris contributed to this story.