The preliminary finding gives investigators a new line of inquiry as they study a crash that killed all but one of the plane’s passengers.

Investors and the wider public are looking for answers after Thursday’s crash of an Air India 787 jet. Both of the plane’s black boxes have been recovered.

India’s government is urgently inspecting all Boeing 787s after a devastating Air India crash that claimed at least 270 lives this week, the aviation minister said on Saturday, adding that the authorities were investigating all possible causes.