Prosecutor: Co-pilot crashed Germanwings flight on purpose

Black-box data revealed the co-pilot of a Germanwings flight slammed into an Alpine mountainside intentionally, leaving questions as to why he did it. Marseille prosecutor Brice Robin said that though co-pilot Andreas Lubitz manually steered the plane downward, nothing indicated it was a terrorist attack. The commander, who has not been identified, left the cockpit, presumably to go to the lavatory, and then was unable to regain access.

It was the co-pilot's “intention to destroy this plane,” Robin said.

The information was pulled from the black box cockpit voice recorder, but Robin said the co-pilot did not say a word after the commanding pilot left the cockpit.

“It was absolute silence in the cockpit,” he said.

During the final minutes of the flight's descent, pounding could be heard on the door as alarms sounded, he said. Passengers on the plane were screaming in the background.

In the German town of Montabaur, acquaintances said Lubitz was in his late 20s and showed no signs of depression when they saw him last fall as he renewed his glider pilot’s license.

A member of the local glider club, Peter Ruecker, said Lubitz had obtained his glider pilot’s license as a teenager, and was accepted as a Lufthansa pilot trainee after finishing a tough German college preparatory school. He described Lubitz as a “rather quiet” but friendly young man.

The Airbus A320, on a flight from Barcelona to Duesseldorf, began to descend from cruising altitude after losing radio contact with ground control and slammed into the remote mountain on Tuesday morning, killing all 150 people on board.

The Associated Press contributed to this report.