Investigators say flight recorders from an Egyptian plane that crashed into the Red Sea on 3 January show terrorists played no role in the disaster.
The first retrieved box appeared to be badly damaged
"It is very obvious there is no outside intervention of any kind," the head of the French-Egyptian investigating team, Shaker Qelada, told AFP.
"What we are looking at is a classic plane accident. It could be a technical defect or human error or both."
A total of 148 people, mostly French holidaymakers, died in the crash.
A French submarine robot retrieved one "black box" flight recorder from a depth of more than 1,000 metres on Friday, and a second one two days later.
French investigator Gerard Legauffre said "the first quick reading of the black boxes and the cockpit voice recorder" showed there was no outside intervention.
Engines to be raised
Investigators had previously all but ruled out terrorism.
French officials said two weeks ago that it appeared the plane had crashed as a result of a sudden loss of power.
An operation will now be carried out to bring large chunks of the engines - lying close to one another at a depth of 1,030 metres - to the surface.
"It is obvious the plane has not exploded in the air," Mr Qelada said.
He added that the plane must have gone "down in
one piece" because investigators found very little debris floating on the water.
A full analysis of the flight recorders would take time, he said.