Jean-Paul Troadec, the former chief of France’s air accident investigation unit, the BEA, said the disappearance was “almost certainly” caused by “an attack”.
Mr Troadec, one of the most respected names in aviation, said the lack of live emergency alert suggested a “brutal event”.
He told Europe 1 radio station in Paris: “A technical problem, a fire or a failed motor do not cause an instant accident, and the team has time to react.
“The team said nothing, they did not react, so it was very probably a brutal event and we can certainly think about an attack