State fire marshals believe they know what started a blaze in Gogebic County that killed an elderly woman over the weekend.
They say she accidentally lit her oxygen tank’s breathing line on fire with a cigarette.
It happened on Roddis Road in Watersmeet at about 12 noon Central time Saturday.
Police say 73-year-old Margaret McNicholas was from Illinois but was staying with her husband at a vacation home they owned.
She was there, on a couch, when the cigarette started an intense fire that burned itself out.
Her husband wasn’t home at the time and found his wife dead when he got back.