France plane crash: What we do and do not know about flight 4U9525

A Germanwings passenger plane travelling from Barcelona to Dusseldorf has crashed in the French Alps.

What we know

• The plane was carrying 144 passengers and six crew. It's thought there were no survivors.

• According to Germanwings, the Airbus A320 went into eight-minute descent before crashing.

• The plane was checked by technicians on Monday, the captain had 10 years' experience and had clocked up more than 6,000 hours of flying Airbus models.

• The plane had been in use since 1991.

• It is thought a party of 16 schoolchildren and their teachers as well as two babies were on board but the flight list will not be released immediately.

• Contact between the plane ended at 10.53am local time, around 52 minutes after the plane departed.

• Debris has been located on the Alps at an altitude of around 6,500ft (2000m) following passenger plane crash. The area where the plane went down is near a popular ski resort.

• More than 300 police officers and firemen, including teams trained to work in the high mountains, are on their way to the scene

• Since news of the crash broke, shares in both Lufthansa and Airbus have dropped.

What has been said

French president Francois Hollande and prime minister Manuel Valls have both said it is unlikely any of the 150 people on board survived.

"It's a tragedy on our soil," Hollande said, adding there were likely a number of German victims.

Spain's Kings Felipe, who was in Paris at the start of a three-day visit, has said the victims are mostly “German, Spanish and Turkish”.

France's transport minister Alain Vidalies said the aircraft had been flying unusually low when it sent out a distress signal. "There was a distress signal at 10.47am. It indicated that the aircraft was flying at 5,000 feet, which was abnormal. The crash occurred soon afterwards.”

Germanwings is a subsidiary of Lufthansa, Europe's largest airline, which confirmed the crash in a statement. They said in a statement the plane had been in use since 1991.

What we don't know

• The full extent of the casualties
• What caused the crash and the circumstances leading up to it
• The nationalities of the victims

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