Co-pilot Andreas Lubitz, seen in an image from his Facebook page, is reported to have controlled the plane's descent toward crash.
Officials investigating the crash of the Germanwings flight say the plane's co-pilot, Andreas Lubitz, wanted to "destroy the plane."
Details are emerging of the German co-pilot's past, and his motives for causing the crash remain a mystery.
Reuters reports that police are searching Lubitz's home for evidence that may help investigators understand why the young German locked himself alone in the cockpit of flight 9525, then and set it on course to crash into the French Alps, killing all 150 people on board including himself.
French and German officials said there was no indication he was a terrorist. Acquaintances described Lubitz as an affable young man who had given no sign of harboring harmful intent.
According to Marseille prosecutor Brice Robin, Lubitz acted "for a reason we cannot fathom right now but which looks like intent to destroy this aircraft".
Setting the plane's controls for rapid descent was an act that "could only have been voluntary", Robin said. "He had… no reason to stop the pilot-in-command from coming back into the cockpit. He had no reason to refuse to answer to the air controller who was alerting him on the loss of altitude."
The 'black box' for Germanair flight 9525.
And from the BBC's coverage:
Marseille prosecutor Brice Robin, citing information from the "black box" voice recorder, said the co-pilot was alone in the cockpit.
He intentionally started a descent while the pilot was locked out.
Mr Robin said there was "absolute silence in the cockpit" as the pilot fought to re-enter it.
