Many Years Ago,

in 1991 as it happens,

there was a film called Backdraft, about firefighters, but what exactly is a backdraft? a brief answer, a backdraft can occur when a compartment fire has little or no ventilation, leading to slowing of gas-phase combustion (due to the lack of oxygen); however, the combustible fuel gases (unburnt fuel vapor and gas-phase combustion intermediates such as hydrocarbons and carbon monoxide) and smoke (primarily particulate matter) remain at a temperature hotter than the auto-ignition temperature of the fuel mixture. If oxygen is then re-introduced to the compartment, e.g. by opening a door or window to a closed room, combustion will restart, often rapidly, as the gases are heated by the combustion and expand rapidly because of the rapidly increasing temperature, 

and this is a near perfect example of how dangerous a backdraft can be, thankfully nobody was killed during this incident that happened last week.