By LORI HINNANT and CLAUDE PARIS

    A Germanwings jet carrying 150 people from Barcelona to Duesseldorf slammed into a remote section of the French Alps on Tuesday, sounding like an avalanche as it scattered pulverized debris across a rocky mountain and down its steep ravines. All aboard were assumed killed.
    The pilots sent out no distress call and had lost radio contact with their control center, France's aviation authority said, deepening the mystery over the A320's mid-flight crash after a surprise 8-minute descent.
    "The site is a picture of horror. The grief of the families and friends is immeasurable. We must now stand together. We are united in our great grief," German Foreign Minister Frank-Walter Steinmeier said in a statement after being flown over the crash scene and briefed by French authorities.
    The crash left officials and families across Europe reeling in shock. Sobbing, grieving relatives at both airports were led away by airport workers and crisis counselors. One German town was rent with sorrow after losing 16 high school students coming back from an exchange program in Spain.
    "This is pretty much the worst thing you can imagine," a visibly rattled Haltern Mayor Bodo Klimpel said at a hastily called press conference.
    As helicopters were deployed to reach the crash site, German Chancellor Angela Merkel urged reporters not to speculate on the cause.
    "We still don't know much beyond the bare information on the flight, and there should be no speculation on the cause of the crash," she said in Berlin. "All that will be investigated thoroughly."