A preliminary report released last week included detail about the fuel, saying that the fuel to the plane's engines appeared to have been shut off.

An official report on the world’s deadliest aviation accident in a decade, seen by CNN, has answered one key question – but raised others.

A preliminary investigation released last week by India's Aircraft Accident Investigation Bureau found confusion in the cockpit shortly before the June 12 crash, and raised fresh questions over the position of the critical engine fuel cutoff switches.