An Airbus A320 operated by the Germanwings airline, a budget subsidiary of German carrier Lufthansa, crashed Tuesday in the French Alps.
The French aviation authority confirmed the flight from Barcelona, Spain, to Dusseldorf, Germany had crashed.
The Associated Press cited regional official Eric Ciotti as saying wreckage from the plane had been discovered at Meolans-Revels, near a popular ski resort and west of the town of Digne-les-Bains. The actual wreckage was believed to be on the side of a mountain, inaccessible by roads and covered in heavy snow.
Germanwings said the plane was carrying 144 passengers and six crew members, raising by two a total headcount given earlier by French officials.
French President Francois Hollande said search and rescue teams did not expect to find any survivors from the crash.
"It's a tragedy on our soil," the French leader said, adding that he would be in contact with his German counterpart Angela Merkel, as he expected many of the victims of the crash were German.
A spokesman for Spain's Deputy Prime Minister Soraya Saenz de Santamaria said there were at least 45 people on the plane "with Spanish surnames," however, according to the Reuters news agency.
There was no immediate indication as to what might have caused the crash. French media said the flight's crew issued a distress call to air traffic controllers at 9:47 a.m. GMT (5:47 a.m. Eastern), and that the jet dropped abruptly in altitude before disappearing from radar.
French Interior Ministry spokesman Pierre-Henry Brandet said the jet crashed in the mountains at an altitude of about 6,550 feet. Crews were struggling to access the crash location due to the rugged terrain.
Brandet told BFM television that he expected "an extremely long and extremely difficult" search and rescue operation because of the area's remoteness.
Airbus told CBS News in a statement that the manufacturer was "aware of the media reports and all efforts are now going towards assessing the situation."
The Airbus A320 is a workhorse of the short and medium-haul passenger aviation business. More than 3,000 of them are in daily operation with airlines around the world.
"Age doesn't matter, maintenance matters" when it comes to passenger aircraft, CBS News travel editor Peter Greenberg said, adding that crash investigators would be looking closely at recent service logs for the plane.
Both Germanwings and its parent company Lufthansa have strong safety records.