The copilot intentionally took the Germanwings A320 plane down, causing it to crash Tuesday in the French Alps, said the prosecutor of Marseille, Brice Robin, who is responsible for the investigation, Anadolu agency reported.
In a press conference, Robin said that the last 30 minutes of black box recordings show that the copilot was in control of the flight when the crash happened.
According to Robin, the first 20 minutes of the conversation between the pilot and copilot was normal, then the pilot left to toilet and the copilot took over.
The prosecutor said at that point the copilot, using the keys of the monitoring system, "voluntarily" put the aircraft into a dive, and he was alive until the moment of impact.
"The copilot intentionally kept the pilot outside the cockpit and took the Germanwings plane into a dive," Robin said. "The intention was to destroy this plane."
"He operated the button controlling the loss of altitude from 12000m to 2000m," explained Robin.
The prosecutor said that the copilot didn't send a distress call, and ignored the one sent by aviation officers in the ground.
Robin identified the copilot as Andreas Lubitz, 28, a German citizen.
According to Lufthansa, the parent company of the low-budget Germanwings, Lubitz joined Germanwings in 2013 and had 630 flight hours. He completed flight training with Lufthansa in Bremen, Germany. He comes from the town of Montabaur, about 60 miles northwest of Frankfurt.
"We can hear him breathing in the cockpit until the last moment of the crash," the prosecutor added. "There was an absolute silence inside the cockpit. Nothing, no word during the last 10 minutes."
"However, this was not a terrorist act," the prosecutor said. "He is not known as a terrorist, absolutely not," Robin said. Asked if it was a suicide, the prosecutor said that he could not make a determination.
Robin added the death of the passengers was "sudden and immediate."
"We can hear cries only in the very last moments," he said.
After the revelations of the prosecutor, Spanish PM Mariano Rajoy tweeted he is "deeply shocked" by the findings of the investigation.
The Germanwings airlines issued a statement, reading : "We are shaken by the upsetting statements of the French authorities, our thoughts and prayers continue to be with the families and friends of the victims."
Meanwhile, search-and-rescue teams are continuing to recover the bodies of the victims, an effort which will take until the end of next week, according to the prosecutor.
Families of the victims as well as of the crew arrived at Marseille on Thursday and met the prosecutor. They are due to visit the crash site near Seyne-les-Alpes during the day.
On Wednesday, recordings from the cockpit voice recorder of the crashed plane have been successfully extracted from the first black box and "usable data" were extracted from it, announced Remi Jouty director of the Bureau of Accident Investigations, France's civil aviation regulator.
"We managed to get some audio, usable data, but it's still too early to draw conclusions as to what happened," said Jouty.
Seven BEA investigators along with investigators from their German and Spanish counterpart, the BFU and the CIAIAC, as well as the Interpol are working on the ongoing probe.
The Germanwings Airbus 320, en route from Barcelona, Spain, to Dusseldorf, Germany, went down Tuesday before 11:00 a.m. local time (10:00 GMT) after an eight-minute descent, killing all 150 people on board, the majority of whom were German and Spanish.
The air disaster is one of the most tragic incidents in recent German aviation history, and the first deadly crash of a Germanwings plane since the low-budget airline was founded by Germany's largest airline in 2002.
A copilot and a passenger died when Lufthansa Airbus A320-200 overran a runway at an airport in Warsaw, Poland, in 1993. A total of 68 occupants survived.
The crash was also the first on French soil since July 25, 2000, when an Air France Concorde crashed into a hotel in Gonesse in the Val-d'Oise, shortly after taking off from Roissy-CDG airport, killing 13 German passengers and crew members, along with four others on the ground.
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