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.

DNA tests have confirmed the identities of 163 victims of the tragic Air India crash in Ahmedabad, an official said on Tuesday. So far, the mortal remains of 124 victims have been handed over to their families.