DUESSELDORF, Germany

- How could someone once diagnosed with suicidal tendencies get a job as a commercial pilot, entrusted with the lives of hundreds of people? That's the question being asked after officials confirmed yesterday that Germanwings co-pilot Andreas Lubitz received lengthy psychotherapy before receiving his pilot's license.

All 150 people on board were killed by what prosecutors believe was a deliberate decision by Lubitz to slam the Airbus A320 he was flying from Barcelona to Duesseldorf into a mountain in the French Alps last Tuesday.

Lufthansa, Germanwings' parent company, declined to say whether it knew of Lubitz's mental-health problems. But it said the young pilot had passed all required medical checks since he began work for its subsidiary two years ago.

Prosecutors in Duesseldorf, where Lubitz had an apartment, said the psychotherapy occurred over an extended period before he received his pilot's license, and that medical records referred to "suicidal tendencies." They provided no dates.

Lubitz started pilot training in 2008, and Lufthansa said he was certified to fly their aircraft in 2013.