Louisville, KY (AP) -- Kentucky authorities say a burning cigarette looks like the cause of a house fire that killed ten people earlier this month.

A Deputy Fire Marshall says the cigarette was left burning near a chair in the Bardstown, Kentucky, home. Rob Goodwin calls it the "hot energy source" from which the blaze grew.

Four adults and six children in an extended family all died from smoke inhalation. One person survived with non-life-threatening injuries.

Fire officials estimate the cigarette burned for about 40 minutes before anybody noticed. It produced toxic smoke, and the fire eventually spread to the furniture and walls before engulfing the house.

Goodwin says it appears the victims tried to escape. But he says it only takes a couple of breaths of the toxic smoke for a person to become dizzy and disoriented.

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