Postpublished at 12:40 Greenwich Mean Time 24 March 2015
Germanwings now says there were 144 passengers and six crew aboard Flight 4U 9525.
A Germanwings Airbus A320 has crashed in the French Alps near Digne, with 150 people on board
Flight 4U 9525 was travelling between Barcelona and Duesseldorf
Passengers believed to include 67 Germans and 45 Spanish citizens
French President Francois Hollande said he believed none of those on board had survived
Sixteen German students on a Spanish exchange trip on flight
Opera singers Oleg Bryjak and Maria Radner also on board
Search-and-rescue teams reach the crash site at Meolans-Revels
Cologne-based Germanwings is a low-cost airline owned by Lufthansa
Saira Asher, Claire Brennan, Alex Kleiderman, Caroline McClatchey, Josephine McDermott and Thom Poole
Germanwings now says there were 144 passengers and six crew aboard Flight 4U 9525.
UK Prime Minister David Cameron's thoughts are with the friends and family of those involved in the crash, his spokesman says. It was not yet known whether there were any UK nationals on board but the Foreign Office would be talking to counterparts in France.
Le Monde newspaper have tweeted that the incident is the worst airplane crash in terms of fatalities on French soil since 1981, when 180 people died in a plane accident near Ajaccio.
The Civil Protection Service in Catalonia says concerned relatives can call an information line on 0049 30 5000 3000.
Reports from Spain suggest 45 Spanish passengers were on board the flight. Barcelona airport has set up a room in Terminal 2 for family members, according to officials in Catalonia.
Low-cost budget airline created in 2002 and wholly owned by Lufthansa
Based in Cologne, it operates increasing numbers of the group's point to point short haul routes
Popular with German tourists heading to Mediterranean cities and resorts
Lufthansa Group announced in January 2015 that it planned to phase out the Germanwings brand and replace it with Eurowings
European Commissioner for Transport Violeta Bulc tells reporters in Brussels that officials were working with the French, Spanish and German authorities.
French President Francois Hollande has spoken briefly with German Chancellor Angela Merkel to express solidarity following the crash of the Germanwings plane. Meanwhile, Spain's King Felipe and his wife are in France on a scheduled visit and are meeting Mr Hollande.
Germanwings is due to hold a news conference at 14:00 GMT at Cologne-Bonn airport, French satellite channel BFMTV says.
The arrivals board at Duesseldorf airport shows no flight status for 4U9525.
German air safety experts are on the way to the crash site, says Reuters, citing the transport ministry.
BBC Business reporter Nigel Cassidy:
Germanwings has an excellent safety record with no previously reported accidents. The average age of its Airbus fleet is just over nine-years-old though flight 4U9525 was being flown by a 24-year-old A320.
Reuters has more details about the ownership of plane. According to online database airfleets.net, the Airbus A320 had been with the parent Lufthansa group since it was manufactured in 1991.
Captain Benoit Zeisser of the Digne-le-Bains police tells French TV network iTele the cloud ceiling in the crash area was not low and there did not appear to be turbulence.
French Interior Ministry spokesman Pierre-Henry Brandet is quoted by Associated Press saying debris from the crash has been located. The crash site in the Alps was at an altitude of 2,000m (6,560ft).
Daily Mirror chief reporter Andy Lines
tweets, external: Bodies of victims are being taken to an emergency morgue set up at a gymnasium in village of Seyne-Les-Alpes.
tweets, external: We do not yet know what has happened to flight 4U 9525. My deepest sympathy goes to the families and friends of our passengers and crew on 4U 9525. If our fears are confirmed, this is a dark day for Lufthansa. We hope to find survivors.