The cockpit crew at first didn’t realize there was a fire outside the engine and the captain initially ordered passengers not to evacuate, NTSB said. After smoke became visible around the plane and a pilot who had gone into the cabin reported the fire, the captain called for an emergency evacuation.

With fire blocking some exits on the left side and the still-running right engine blasting wind against the rear two exits on that side of the plane, passengers had to escape through only two of the eight doors, the NTSB found. In the chaotic moments of the emergency, pilots also didn’t perform proper checklists, according to the investigation.