The co-pilot of the doomed Germanwings flight appears to have "deliberately" crashed the plane into the French Alps after locking his captain out of the cockpit, French officials say.
Lead prosecutor Brice Robin on Thursday said 28-year-old Andreas Lubitz initiated the plane's descent while alone at the controls. But officials do not believe the co-pilot he was part of a terrorist plot.
The young German appeared to "show a desire to want to destroy" the plane, Mr Robin said, basing his findings on sound recordings from the Airbus A320's cockpit flight recorder in the minutes before the crash that killed all 150 passengers and crew on board.
The Marseille prosecutor said those on board Germanwings Flight 4U 9525 died "instantly" and probably were not aware until the "very last moment" of the impending disaster.
"The screams are heard only in the last moments before the impact," he said.
"The co-pilot was alone at the controls," he said. "He ... refused to open the door of the cockpit to the pilot."
The pilot, believed to have gone to the toilet, made increasingly furious attempts to re-enter the cockpit, banging on the door, the recordings show.
There was no immediate clue as to the motive of the co-pilot, but investigators appeared to rule out terrorism.
"At this moment, there is no indication that this is an act of terrorism," Mr Robin said, adding that the co-pilot had no known terrorist connection.
Andreas Lubitz, a German national who joined the budget carrier in September 2013, had just 630 hours of flying time - compared with the 6,000 hours of the flight captain, named in German media only as "Patrick S." in accordance with usual practice.
Mr Robin said he could not guess at Mr Lubitz's motive. The co-pilot, who deliberately set the controls "to accelerate the plane's descent" into the side of a mountain, "was conscious until the moment of impact."
"This action can only be deliberate." said Mr Robin. It would be impossible to turn the button by mistake. If you passed out and leaned over on it, it would only go a quarter-turn and do nothing," he stressed.
"He didn't reply to a thing. He didn't say a word. In the cockpit, it was utter silence."
The chief executive of Lufthansa, parent company of Germanwings, said its air crew were picked carefully and subjected to psychological vetting.
"No matter your safety regulations, no matter how high you set the bar, and we have incredibly high standards, there is no way to rule out such an event," said Carsten Spohr.
Pilots may temporarily leave the cockpit at certain times and in certain circumstances, such as while the aircraft is cruising, according to German aviation law.
Cockpit doors can be opened from the outside with a code, in line with regulations introduced after the Sept. 11, 2001 attacks in the United States. The code can be overridden from inside the cockpit.
Lufthansa's CEO Carsten Spohr said that either the pilot had entered the code incorrectly, or the co-pilot inside had overridden it.
The shocking new information was released as families and friends of victims travelled to the remote mountainous crash site area. Two planes arrived in southern France on Thursday from Barcelona and Duesseldorf with families and friends.
Tents were set up for them to give DNA samples to start the process of identifying the bodies of loved ones, at least 51 of whom were Spaniards and at least 72 Germans.
- AFP / Reuters