An Airbus traveling from Barcelona to Düsseldorf crashed in the Bleone Valley in southern France on Tuesday after the pilot lost contact with air traffic control. 

The A320 jet is operated by Lufthansa's Germanwings, a low-cost airline, and carried 144 passengers and six crew members. 
According to The Huffington Post, representatives for the airline reported that the plane began descending immediately after reaching cruising height and continued to lose altitude until it crashed, though the exact cause is not yet known. 

French officials said there were no expected survivors. 

The Associated Press reported that the plane crashed at an altitude of about 2,000 meters near a popular ski resort in the French Alps. 

One witness who heard the crash told AP it was "deafening," saying "I thought it was an avalanche, although it sounded slightly different. It was a short noise and lasted just a few seconds." 

Passengers are believed to be mostly German or Spanish nationals, and may have included a group of 16 high school students returning to Germany after a study abroad trip to Spain. 

German Chancellor Angela Merkel expressed "shock" and "deep sorrow" over the news, and ensured there would be a thorough investigation into the cause of the crash.