Investigators are attempting to uncover more information about the co-pilot who appears to have deliberately crashed the ill-fated Germanwings passenger jet.

A French prosecutor turned the spotlight on 28-year-old Andreas Lubitz who was at the controls of the plane that was carrying 150 passengers and crew.

Details of the last 10 minutes of the A320 flight came from audio files from the cockpit voice recorder.

The prosecutor, Brice Robin, says Lubitz was left alone at the controls when the captain went to the toilet, shortly after hitting cruising altitude over the French Alps.

The co-pilot refused to unlock the cockpit door when the captain returned and the plane was deliberately put into a steady descent.

The prosecutor says it appears Lubitz wanted to “destroy” the aircraft. He was known to be breathing normally right up until the impact.

The sound of the captain attempting to smash the door down, as well as screaming from passengers, are reportedly heard on the co