Germanwings plane crash: One pilot was locked out of the cockpit before Alps crash, black box recordings show

Updated: Officials confirm newspaper reports that audio indicates one of the pilots was not able to re-enter the cockpit before the crash

Voice recordings from one of the black boxes of the Germanwings plane that smashed into the Alps show that one of the pilots left the cockpit and was unable to return as the plane went down.

French aviation officials who had worked on the audio recordings confirmed newspaper reports that revealed the crucial details of the plane's final moments.

Quoted the New York Times, a senior military official said evidence from a cockpit voice recorder had revealed audio from the Airbus A320's gradual 11-minute descent into the side of a mountain in the French Alps.

Q&A: How could a pilot get locked out of the flight deck?

"And then he hits the door stronger and no answer. There is never an answer.

"You can hear he is trying to smash the door down," the investigator added.

The official does not speculate as to why the other pilot didn't open the door or make contact with ground control before the plane crashed on Tuesday.

The report says there was no indication from the audio as to the reason why the pilot left the cockpit. The paper claims the official was speaking on condition of anonymity as the investigation was ongoing.

While officials have now repeated a similar version of events to both the AFP and AP news agencies, Lufthansa said on Thursday that it had received no new information from investigators and could neither confirm nor deny the reports.

The report comes after officials said earlier that they had managed to extract pilots’ voices from the mangled "black box" of the doomed Germanwings Airbus.

They have so far officially been at a loss to explain why the aircraft flew into the mountain in the French Alps, killing all 150 people on board.

It was reported today that among those killed on the flight were three Britons. Other victims included 72 Germans, 35 Spaniards and people from 12 other nationalities.

Reports from the scene stated that the first bodies were being removed last night in a recovery effort hampered by difficult terrain and bad weather.

The development came after French President Francois Hollande, Germany's Angela Merkel and Spain's Mariano Rajoy travelled to the crash site in a remote French Alpine region to pay tribute to the 150 victims.

President Hollande promised that authorities would not rest until the causes of the crash were known, France's BEA air incident investigation bureau said it was still far too early to draw meaningful conclusions on why the plane, operated by the Germanwings budget arm of Lufthansa, went down.

"We have just been able to extract a useable audio data file," BEA director Remi Jouty told a news conference at the agency's headquarters outside Paris.

"We have not yet been able to study and to establish an exact timing for all the sounds and words heard on this file."

Jouty expected the first basic analysis in "a matter of days" but warned this read-out could be subject to errors and that more work would be needed for a full interpretation.

Although he said "words" had been heard on the tape, Jouty would not confirm whether that meant the Airbus A320's pilots were conscious and he gave no details of the recordings.

Interior Minister Bernard Cazeneuve earlier said a terror attack was not the main hypothesis. Jouty said, however, that no theory could be excluded yet.

While stressing it was too early to form a clear picture, he ruled out a mid-air explosion and said the crash scenario did not appear to be linked to depressurisation.

In what seemed an accelerated push to extract as much early information as possible from the cockpit tapes, BEA officials worked late into the evening at their offices.

Additional reporting by AP, Reuters