The second black box belonging to Germanwings flight 4U 9525 confirms that co-pilot Andreas Lubitz acted deliberately, investigators say.

The French BEA crash investigation agency said Andreas Lubitz repeatedly accelerated the plane’s descent before crashing into the French Alps.

The second flight recorder from the plane was recovered on April 2.

All 150 people on board the flight from Barcelona to Duesseldorf on March 24 were killed.

“A first reading shows that the pilot in the cockpit used the automatic pilot to put the airplane on a descent towards an altitude of 100ft,” the BEA said in a statement on April 3.

“Then several times the pilot modified the automatic pilot settings to increase the speed of the airplane as it descended,” it added.

Earlier findings from the cockpit voice recorder suggested Andreas Lubitz, 27, locked the pilot out of the cockpit.

On April 2, German prosecutors said Andreas Lubitz had researched suicide methods and the security of cockpit doors on the internet the week before the crash.

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