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.

The much-awaited preliminary report on the devastating Air India crash, involving a Boeing Co. BA +1.68% Get Free Report airplane, in June, which claimed 260 lives, is expected to be released by the end of this week.

Boeing stock was in a holding pattern on Tuesday as investors waited for details from flight data recorders from Air India flight 171, which crashed on June 12, less than a minute after taking off from an airport in Ahmedabad,