Pilot locked out of cockpit in French Alps plane crash

SEYNE-LES-ALPES, France -- One of the pilots of the Germanwings flight that crashed in the French Alps may have been locked out of the cockpit, a senior military official involved in the investigation told The New York Times.

The official said that the audio on the cockpit voice recorder indicated one of the pilots was outside of the cockpit and unable to re-enter, according to the paper. The unnamed official described hearing the pilot unable to re-enter the cockpit lightly knocked on the door at first - before pounding on it.

"You can hear he is trying to smash the door down," he told the Times.

ABC News was unable to independently confirm the report.

Investigators have not yet recovered the second black box from the Airbus A320, which crashed Tuesday in Southern France while en route to Dusseldorf, Germany. All 150 on board, including three Americans, are believed to have been killed.

Earlier Wednesday, the director of the Bureau d'Enquetes et d'Analyses (BEA) said an audio file from one of the the black boxes, the cockpit voice recorder, had been found, but did not say whether voices were heard on the recording.