All 66 passengers and crew onboard the Airbus A320 were killed when the aircraft, flying from Paris to Cairo, went down in the Mediterranean Sea between Crete and the coast of northern Egypt. 

Italian newspaper Corriere Della Sera reported it had obtained the 134-page investigation report compiled by French air crash experts which has been sent to the Paris Court of Appeal.

The document is claimed to have discovered a fire broke out in the cockpit due to oxygen escaping from the co-pilot’s mask when it is thought a cigarette was being smoked. 

It is believed a “spark or flame” from the cigarette would have caused the oxygen to combust.

According to the report, three days prior the crash, the pilot’s mask was replaced and its setting left on ‘emergency’ instead of ‘normal’ by a maintenance engineer, causing oxygen to be emitted and leading to the fire. 

France’s Bureau of Enquiry and Analysis for Civil Aviation Safety had initially suspected a mechanical failure or inadequacy had led to the crash, while Egyptian authorities claimed the plane had been the subject of a terrorist attack.