A BBC producer says she has seen police officers entering the house. It is in a well-manicured, quiet cul-de-sac on the outskirts of Montabaur, she adds.

German police have been keeping the media away from the door of Andreas Lubitz's home in the town of Montabaur, about 60km (37 miles) north-west of Frankfurt. Neighbours have refused to comment.

Image source, Reuters

Earlier, Germany's Interior Minister Thomas de Maiziere told journalists that Andreas Lubitz was not known to the country's police or intelligence agencies. Neither, he added, had the co-pilot been flagged in any Lufthansa security checks.

Lufthansa CEO Carsten Spohr told a news conference in Cologne that Andreas Lubitz began his training in 2008. "After his training there was an 11-month waiting period - this is not unusual with us - and since 2013 he was working as co-pilot on the Airbus A320."

He added: "I want to mention that there was a longer break in his training six years ago and after his suitability was assessed again he resumed his training. Subsequently, he passed all medical checks as well as all aviation training. He was 100% fit to fly without any restrictions or conditions."

Members of the LSC Westerwald flying club earlier said Mr Lubitz had gained his glider pilot's licence as a teenager and that he had shown no signs of depression when he renewed that licence in the autumn.

The chairman of Mr Lubitz's flying club, Klaus Radke, told AP that he rejected the French prosecutor's assessment that he had deliberately crashed the plane into the Alps. "I don't see how anyone can draw such conclusions before the investigation is completed."

Image source, AFP

Members of Andreas Lubitz's flying club in Montabaur, Germany, say the 28 year old appeared to be content with his job. "He was happy he had the job with Germanwings and he was doing well," longtime LSC Westerwald member Peter Ruecker told the Associated Press. "He was very happy, he gave off a good feeling."

Image source, AFP

Mr Spohr says: "No matter your safety regulations, no matter how high you set the bar, and we have incredibly high standards, there is no way to rule out such an event."

Lufthansa CEO Carsten Spohr tells a news conference in Cologne: "We choose our staff very, very carefully."

Image source, AFP

Mr Spohr says there is no indication about what the co-pilot's motive was.

Image source, Facebook

Lufthansa CEO Carsten Spohr says: "In our worst nightmares we couldn't have imagined that such a tragedy could happen within our company."

Germany's Transport Minister, Alexander Dobrindt, said the French authorities' assessment that the plane's descent into the Alps was initiated deliberately was "according to our experts, plausible". He added: "We are in very close contact with Lufthansa regarding the conclusions that need to be drawn from this tragedy. One can only say that what the French prosecution described in great detail today is indeed more than harrowing."

Lufthansa chairman and CEO Carsten Spohr tells a news conference in Cologne that staff at the airline, and those at its subsidiary Germanwings, are "absolutely speechless" and "deeply shocked" at the news of the co-pilot's actions. "I would not have been able to imagine that the situation could get even worse," he adds.

Just to recap on what we have learnt in the last few hours. Officials in France say the co-pilot of the Germanwings Airbus A320 - which crashed into the French Alps on Tuesday, killing all 150 people on board - appears to have deliberately brought the plane down. Marseille prosecutor Brice Robin said Andreas Lubitz, 28, "voluntarily" sent the plane into a descent, while the pilot was locked out of the cockpit. But he said it did not appear to be a terrorist act.

Image source, EPA

German Transport Minister Alexander Dobrindt says the emerging details of what happened on flight 4U 9525 reveal a situation that is "truly more than shocking".

Image source, AFP

Prime Minister Mariano Rajoy of Spain says via Twitter, external that he is "deeply shaken by the latest information given by the investigators". He added: "Once again, our heartfelt affection to the families". There were 50 Spaniards on board the flight from Barcelona to Duesseldorf.

Image source, EPA

The captain of Airbus A320, who has not been identified, had more than 10 years of experience with German flag carrier Lufthansa and its subsidiaries, including Germanwings. He had more than 6,000 hours of flight time, most of them on Airbus planes.

The AFP news agency reports that the co-pilot, Andreas Lubitz, was registered as a member of a private flying club in Germany, LSC Westerwald, and was a runner who took part in local races, according to public records. This is a screengrab of what is believed to be his Facebook profile.

Image source, Reuters

On its Twitter feed, external, Germanwings says: "We are shaken by the upsetting statements of the French authorities. Our thoughts and prayers continue to be with the families and friends of the victims." The airline will hold a news conference at 14:30 German time (13:30 GMT).

David Gleave, an air accident investigator whose speciality is pilot suicides, says the aviation industry needs to start looking at the psychological profiles of pilots. "We may find that this pilot had various stresses that may have led to some form of relatively irrational behaviour. It could be a vast amount of debt taken out for pilot training, it could be family matters, it could be religious matters. There's all sorts of areas that the psychological specialist will start to look at during the investigation but I certainly think that it's going to be reviewed fairly quickly."