The granddaughter of a victim of the Air India Flight 171 crash has said a preliminary report into the incident was "incomplete" and that she "can't be at peace" without those responsible being held accountable.

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

Authorities released a preliminary report on the Air India crash, following an investigation. The London-bound flight from Ahmedabad crashed minutes into the June 12 flight. Only one passenger of the 242 passengers and flight crew survived.