Fire reports in the US NFPA Journal note two recent cases of fatal home fires where implication of upholstered furniture has been identified by fire fighters. In New York, a laptop battery placed on a couch had heated and ignited the couch.
The resident of the house died of inhalation and smoke. In South Carolina a house fire in which the resident died of inhalation and smoke was identified by fire fighters to have been caused by a cigarette igniting a couch. The fire had not spread beyond the couch, which was still smouldering when firefighters arrived.
US National Fire Protection Association “Firewatch”, NFPA Journal Nov-Dec. 2017 http://www.nfpa.org/News-and-Research/Publications/NFPA-Journal/2017/November-December-2017/News-and-Analysis/Firewatch