SEYNE-LES-ALPES, France (AP) — Authorities so far have few clues as to what brought down a German jetliner carrying 150 people in a remote section of the French Alps today. All of those aboard are assumed to have been killed in the crash — which took place after the plane descended for eight minutes.

French aviation officials say the pilots sent out no distress call and had lost radio contact with their control center.

The crash left pulverized debris scattered across a rocky mountain and down the steep ravines.

As helicopters were deployed to the crash site, German Chancellor Angela Merkel urged reporters not to speculate on the cause of the crash. An official with Lufthansa — which owns the airline Germanwings — says for now, it’s being treated as “an accident.” And the White House says there’s no indication of terrorism.

France’s Interior Ministry says a black box has been found at the crash site. There’s no word on whether it’s a data or cockpit voice recorder.

The airline says the plane left Barcelona at 10 a.m., and after reaching its cruising altitude of 38,000 feet it began descending again. It crashed at an altitude of about 6,500 feet near a popular ski resort.