Andreas Lubitz, the co-pilot accused of deliberately crashing a Germanwings flight into the French Alps last week and killing all 150 people on board, received treatment for suicidal tendencies before obtaining his pilot license, according to German prosecutors. It has been emphasized, however, that this therapy took place in the past and did not occur recently.
Speaking at a news conference on Monday, Christoph Kumpa, the prosecutors' spokesman, told reporters: "There still is no evidence that the co-pilot [said] 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... be it personal, or [from] his family, or his professional surroundings, that is giving us any hints that enable us to say anything about his motivation. We have found medical documentation that shows no organic medical illness," he added.
This news coincides with the further release of details of the final moments of Germanwings flight 4U9525 from Barcelona, Spain, to the German city of Düsseldorf last Tuesday. A leaked transcript of the cockpit voice recorder from the aircraft apparently reveals how co-pilot Lubitz did not let Captain Patrick Sondenheimer back into the cockpit, despite frantic pleas.
In the transcript, leaked to the German newspaper Bild and yet to be independently verified, Sondenheimer can be heard shouting: "For God's sake, open the door!" He then tried to break into the cockpit with an axe as Lubitz remained silent.
Earlier, as revealed in the transcript, the captain told Lubitz that he was unable to go to the bathroom before takeoff and Lubitz offered to take over so he could do so. When the plane reached 38,000 feet, Sondenheimer briefed Lubitz on the landing in Düsseldorf and the co-pilot apparently encouraged his colleague to go to the bathroom. Two minutes later, Sondenheimer said: "You can take over." The cockpit door closed and the plane appears to have shortly began its descent.
Last week, French prosecutor Brice Robin, who has been handling the investigation, suggested that Lubitz deliberately crashed the aircraft: "The most plausible interpretation is that the co-pilot voluntarily refused to open the door for the captain and activated the button controlling the plane's altitude for a reason we don't know," he said, interpreting the action as "a desire to destroy the plane."
Forensic teams have now identified the DNA of 78 victims from the crash site. Recovery teams are also trying to locate the missing second black box, which contains flight data. However, an official from the company Lufthansa, which owns Germanwings, has said that the second black box may be too badly damaged for retrieval.
Prosecutor Robin said an access road was being built to the crash site in the remote mountains in the south of France.
Since last week's revelations there has been a large amount of speculation regarding Lubitz's mental health. Torn-up sick notes were discovered in his Düsseldorf apartment which would have prevented him from flying on the day of the crash. Medication has also been found at his apartment and prosecutors have indicated that Lubitz had "hidden his illness from his employer and his colleagues."
It has also been reported that he suffered from depression around the time that he suspended pilot training in 2009.
Further details of Lubitz's medical history emerged at Monday's news conference. Kumpa told reporters: "The co-pilot has been, before he got his pilot's license, 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... But these documents don't show any hint of being suicidal or being aggressive against other people."
Further reports have suggested that Lubitz suffered from eye problems and possibly a detached retina. Two officials told the New York Times that this could have jeopardized his ability to continue being a pilot, although on Monday, Kumpa indicated that there was no evidence that he was suffering any problems with his sight.
It was recently reported that the university hospital in Düsseldorf handed investigators medical records relating to three visits made by Lubitz in February and March, yet details of his visits have not yet been disclosed. Dirk Fischer, of the German political party CDU, has called for the easing of medical confidentiality and data protection rules over sensitive jobs, such as pilots.
Last week, however, a statement released by three UK mental health charities raised concerns of the overly simplistic nature of linking depression with the crash: "Clearly assessment of all pilots' physical and mental health is entirely appropriate — but assumptions about risk shouldn't be made across the board for people with depression, or any other illness. There will be pilots with experience of depression who have flown safely for decades and assessments should be made on a case by case basis."
There have also been calls to have two crew members in the cockpit at all times. Within 24 hours of the crash, regulators in Canada and New Zealand introduced the rule, and the European aviation authority has also recommended the change, according to Reuters. On Monday, the Australian transport minister Warren Truss announced that all domestic and international passengers planes, carrying more than 50 people, should have two crew members in the cockpit.
"There is a need to balance the fact that people with proper treatment can recover from mental illness and be able to undertake normal careers with the critical priority of ensuring that aircraft are always safe," Truss said.
Follow Jenna Corderoy on Twitter: @JennaCorderoy