Investigators in India are studying the black boxes of a Boeing 787 Dreamliner after recovering them from the aircraft wreckage to ascertain the cause of last week's plane crash that left at least 270 people dead.

Investigations are intensifying into the crash of Air India Flight 171, which went down just seconds after take-off from Ahmedabad, killing 270 people and leaving many questions unanswered.

Investigators have recovered the cockpit voice recorder (CVR) from the crashed Air India flight, a key step in uncovering what caused last week's deadly accident. The London-bound Air India aircraft,