PORT ORCHARD — Fire investigators reported Friday that a smoldering chair fire in a South Kitsap home yesterday that claimed the life of Karen Williamson, 71, was accidental.

Kitsap County Fire Marshal’s office issued a report that concluded the fire at the 3800 block of Locker Road Southeast was caused when a heating pad ignited a smoldering fire in a recliner in Williamson’s home. She is believed to be the owner of the home and was the sole occupant inside at the time of the fire.

According to Fire Marshal David Lynam, the fire was limited to the area immediately around the recliner. Smoke damage throughout the house, however, was extensive.

“Smoke alarms were installed and sounding in the house at the time of the fire,” Lynam said. “We don’t know why she was not able to escape.”

Sheriff’s Office spokesman Scott Wilson said yesterday that Williamson was found by a relative who had gone to the residence to check on her welfare. The deceased woman was discovered face-down with her favorite reclining chair smoldering and the house filled with smoke.

Wilson said the woman was known to have been a heavy smoker. The male relative who had a key to the home entered the residence and attempted to pull her out of the smoke-filled living room, but she was too heavy to extract from the scene.

Sheriff’s deputies, who were first to arrive, also attempted to move her out of the house. The woman was pronounced dead at the scene by South Kitsap Fire and Rescue responders who arrived a little later.