At first it seemed a tragic accident, claiming 150 lives - but as the week drew on it emerged as something altogether more sinister. Channel 4 News looks back at how the Alpine crash unfolded.
Torn up documents, including doctor's notes consenting time off work dated for the day of the French Alps disaster, have been found at the home of Andreas Lubitz, German prosecutors say.
Police start searching properties in Dusseldorf after French authorities describe how Andreas Lubitz "refused to open" the cockpit door of the Airbus A320 and accelerated its descent "intentionally".
Reports that a pilot deliberately crashed the Germanwings Airbus 320 in the French Alps throws the spotlight not only on aircraft security but also on flight-deck manning.
He was a 28-year-old with normal interests. Yet Andreas Lubitz sat, silent and alone, in the cockpit of the Germanwings Airbus during its fatal descent. What more do we know about him?
Human activity - or inactivity - rather than technical failure emerges as the most likely cause of the Germanwings crash. Though none of this can be of any comfort to grieving families of the victims.
The plane crash in the Alps, as well as MH370 and MH17 last year might make you think air travel is dangerous, but the chance of dying on a flight in the developed world is one in 14million.
Foreign Secretary Philip Hammond confirms at least three UK citizens were among the 150 people thought to have died when a passenger plane crashed in the Alps.