The CEO of Air India sought to draw a line under rife speculation around the cause of last month's air disaster in Ahmedebad, saying the preliminary investigation had ruled out a mechanical cause for the crash.

A preliminary assessment in last month’s disaster focusing on fuel being cut to both engines only deepened the mystery for people grieving loved ones.

An Air India executive is still urging its staff not to jump to any conclusions as the investigation into the crash that killed 260 people last month continues. A preliminary report into the June crash found that the plane's fuel control switches had been flipped off one by one.