The German pilot suspected of deliberately crashing a plane in the French Alps last week was treated for suicidal tendencies years ago before he received his pilot¡¯s license, German prosecutors said on Monday.

This was the first acknowledgement from German officials that the pilot, Andreas Lubitz, had suffered bouts of depression and it is likely to intensify a debate about how airlines screen and monitor their pilots.

Investigators believe Lubitz, serving as co-pilot on a Germanwings flight from Barcelona to Duesseldorf on March 24th, locked the captain out of the cockpit and steered the Airbus A320 plane into the side of a mountain while passengers screamed in horror. A total of 150 people died in the crash.