German prosecutors said on Monday that Andreas Lubitz, who has been blamed for last week's crash of a Germanwings passenger jet, had received psychotherapy treatment for suicidal tendencies before he became a pilot.

"Several years ago before obtaining his pilot's license, the co-pilot was in a long period of psychotherapeutic treatment with noticeable suicidal tendencies," said the prosecutor's office in Düsseldorf, the city where Lubitz lived and where the flight had been headed.

Chief prosecutor Ralf Herrenbrück said that Lubitz had not shown signs of suicidal behavior nor aggression since then.

"In the ensuing years and up until recently, he had doctors' visits and was written off sick but showed no sign of suicidal tendencies or aggression towards others," Herrenbrück said.

Herrenbrück added that authorities have found no motive for why Lubitz would have crashed the plane, as investigators believe, nor any sign of physical illness. All 150 people aboard the plane died last Tuesday when it crashed in the French Alps, en route from Barcelona to Düsseldorf.

Bad weather is hampering helicopter access to the crash site, forcing teams to build a road to speed up the search. Rescue workers currently have to hike around 45 minutes to the site through difficult terrain.

Hundreds of family members of the dead have made their way to Seyne-les-Alps, near the crash site.

jr/sb (AFP, Reuters, AP, dpa)