Questions Mount After Lufthansa Reveal About Co-Pilot's Depression

Lufthansa chief executive Carsten Spohr declined to comment Wednesday on when the airline learned of problems plaguing the 27-year-old co-pilot, who is believed to have intentionally crashed the plane into a mountainside in France last week, killing himself and 149 others on board.

"We are learning more every day, but it will take a long, long time to understand how this could happen," Spohr said during a visit to a memorial near the crash site, alongside Germanwings chief executive Thomas Winkelmann. Lufthansa is Germanwings' parent company.

"We're very, very sorry that such an accident could have happened at Lufthansa, where we put so much focus on safety. We are sorry for the losses that occurred and there are just no words to express this," Spohr said.

Lufthansa had said its flight training school knew of Lubitz's problems with depression. The company on Tuesday produced a 2009 email in which Lubitz explained he was ready to resume flight training after a break.

In it, Lubitz informed the school of a "previous episode of severe depression," sparking questions about why his history didn't raise red flags at the airline carrier.

Lufthansa provided the email along with other documents to prosecutors in the German city of Dusseldorf and said it was cooperating fully with the investigation.

Prosecutors said that Lubitz had been in treatment with psychiatrists and neurologists, and that a doctor had noted a suicidal tendency in him before he received his pilot's licence.

Earlier, Spohr said Lubitz had passed all his medical tests, and that he "was fit for flying without any restrictions." Medical records outlining the suicidal tendencies were protected under German confidentiality laws, and it's unclear that Germanwings was aware of that section of Lubitz's file.

He also passed medical and psychological evaluations to obtain a student pilot certificate from the US Federal Aviation Authority in 2010.

In Berlin, a spokeswoman for the German Transport Ministry said it would not consider changes to the country's pilot selection standards until prosecutors in Dusseldorf have finished their investigation.

France's Paris Match and German tabloid Bild published minute-by-minute accounts of the plane's last minutes, which they say are based on quotes and information drawn from a video found on a mobile phone at the crash site.

French prosecutors said they did not possess a mobile phone video recording of the flight's final moments, telling dpa that remnants of mobile phones found at the crash site were likely too damaged to yield footage.

"In the event that someone has such a video, they should turn it over to police without delay," Marseille prosecutor Brice Robin told French media on Wednesday, repeating comments he made to dpa late Tuesday as he dismissed media reports claiming to have seen footage.

The accounts largely reflect statements Robin gave to press last week after listening to a recovered cockpit voice recorder, from which he surmised Lubitz locked himself alone in the cockpit and intentionally changed the plane's trajectory until it slammed into the mountainside. The cockpit was secured, preventing the pilot from re-entering despite increasingly insistent attempts.

Data from the cockpit voice recorder is one of the key pieces of evidence used by prosecutors to reconstruct the flight's last moments. Investigators are still searching for a the contents of a second black box among the remnants of the plane, which shattered on impact.

A spokesman of the French recovery team gathering evidence from the crash site said that there were no longer any human remains "visible." A group of four German investigators specializing in digital and laser tracing also arrived at the site on Wednesday to collect evidence.

In the town of Haltern in the west of Germany, families and friends were to gather late on Wednesday for an ecumenical religious service in memory of the 16 school pupils and two teachers from a local school killed in the crash.

The students from the town's Joseph Koenig Gymnasium had been returning from a trip to Spain.

The service was to be held in the Catholic church of St Sixtus, the same venue as used for a memorial service last Friday with Germany's President Joachim Gauck.

Germany's national memorial service for the dead is set for April 17 in the Catholic cathedral of Cologne with Chancellor Angela Merkel attending.