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BERLIN (AP) – Swiss media: Authorities say all 20 people on board died in the crash of an old-time plane in the Swiss Alps.

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Swiss officials say they’re not aware of any distress call from an old-time prop plane that crashed in the Swiss Alps before it went down, killing 20 people. They also expect the investigation into the cause of the crash to be “relatively complex.”

Daniel Knecht of the Swiss Transportation Safety Investigation Board said the plane appears to have hit the ground near-vertically and at high speed in Saturday’s crash.

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Speaking at a news conference Sunday in the Alpine resort of Flims, near the crash site, Knecht said the vintage plane presumably didn’t have the crash-resistant cockpit voice and data recorders that more modern aircraft have.

He said officials have essentially ruled out a collision with another aircraft or hitting an obstacle such as a wire. He also says there’s no indication of foul play or that the aircraft lost parts or broke up before the crash.

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