A cockpit voice recording of doomed Air India Flight 171 indicates the younger co-pilot asked his more experienced colleague why he turned off the plane’s fuel-supply switches, according to people familiar with the matter.

According to a report published on Wednesday by The Wall Street Journal quoting sources close to United States officials’ early assessment of evidence, the black box audio recording of the last conversation between the two pilots indicates that the captain might have turned off the switches controlling the flow of fuel to the plane’s engines.

Captain Randhawa dismissed the claims as baseless and vowed to take action against the publication, saying the preliminary report on the Air India plane crash makes no mention of the pilots turning of

International airlines from South Korea and India are preparing to inspect its Boeing fleets following findings from the Air India crash investigation.

The deadly Air India crash last month has renewed a decades-old debate in the aviation industry over installing video cameras monitoring airline pilot actions to complement the cockpit voice and flight data recorders already used by accident investigators.