India's Aircraft Accident Investigation Bureau (AAIB) is yet to decide whether flight data and cockpit voice recorders from the Air India flight that crashed last Thursday will be sent overseas for decoding and analysis.

The move came a day after Indian officials told the airline to improve its operations, and as delays and canceled flights are drawing complaints from passengers.

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.