Drugs to treat mental illness were reportedly found at home of the Germanwings co-pilot Andreas Lubitz who is suspected of deliberately crashing a passenger plane in the French Alps last week, a senior investigator has told German daily Die Welt.

“The 27-year-old has been treated by several neurologists and psychiatrists,” the unnamed senior investigator said. 

A woman purported to be Lubitz’s ex-girlfriend told Germany’s leading tabloid newspaper Bild on Saturday that she believes Lubitz was suffering from psychiatric problems before the crash, as he often lost his temper all of a sudden during their talks and started shouting at her. He once told her one day he would “do something” and then “everyone will know my name.”

The prosecutors found a doctor’s notes in Lubitz’s personal belongings, including one that would have kept him off work on the day of the crash of Flight 4U9525. However, those doctor’s notes had all been torn up in his house. Further investigations are under way.