A preliminary report into the deadly crash of an Air India jetliner in June is expected to be released by Friday, three sources with knowledge of the matter said, with one adding the probe had narrowed its focus to the movement of the plane's fuel control switches.

While the report from investigators could be made public on Friday, the three sources cautioned Reuters that plans could change and there was no clarity on how much information would be available in the document,

As the 30-day limit to submit the report of the preliminary investigation into the June 12 Air India accident in Ahmedabad to the Internationa.