The co-pilot in the French Alps plane disaster was treated for suicidal tendencies in the past, German prosecutors have said.
But prosecutors' spokesman, Christoph Kumpa, told a news conference in Dusseldorf that Andreas Lubitz (27) had not been treated recently.
He said: "There still is no evidence that the co-pilot told before that he'll do what we have to assume was done and we haven't found a letter or anything like that that contains a confession."
"Added to this, we have not found anything in the surrounding be it personal, or his family, or his professional surrounding, that is giving us any hints that enable us to say anything about his motivation."
"We have found medical documentation that show no organic medical illness. The co-pilot has been, before he got his pilot's licence, in psychotherapy. He had at that time been in treatment of a psychotherapist because of what is documented as being suicidal at that time."
"In the following time, up to now, right until he took the plane, there have been several visits at medical doctors and we have found as we have already communicated evidence that his doctors documented him to be unable to work and to fly."
"But these documents don't show any hint of being suicidal or being aggressive against other people."
Mr Kumpa added that there was no evidence Mr Lubitz was suffering any problems with his sight - after reports that he had sought treatment for vision problems, which could have threatened his career.
The co-pilot is believed to have deliberately crashed Flight 4U 9525 last week, killing all those on board.
Victim DNA identified
It comes after French prosecutors said the DNA of 78 of the 150 people on board have been identified.
A summary of the transcript of recordings from the voice recorder on board, published by German newspaper Bild, revealed Lubitz began the descent after the captain left the cockpit.
The captain of the jet reportedly screamed at his co-pilot to "open the damn door" as he tried to get in the cockpit.
The older pilot left to use the toilet and then desperately tried to open the cockpit door during Flight 4U 9525's eight-minute descent, according to the black box voice recorder.
Germany's Bild on Sunday newspaper said he is heard shouting "For God's sake, open the door!" as passengers scream in the background.
He then tries to smash through the heavily reinforced door with an axe, while yelling at a silent Lubitz to "open the damn door".
Before leaving the cockpit, the captain is heard telling Lubitz he did not have time to go to the toilet before they left Barcelona for Dusseldorf.
Rescue teams are still searching for the second black box, which records flight data.
