Early reports are that the free turbine wheel came apart in flight and most of it went out the tail pipe. The crew entered autorotation and it appears completed the auto to a hillside. It looks as if all survived the auto. Unfortunately the hillside was steep and they slid/ rolled down to a very steep cliff (looks like 100 feet or so) and then rolled down the cliff and came to rest at the bottom. It appears two of the crew were killed in the fall from the cliff and not the auto. The rear passenger survived and is still critical.
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Our prayers are with the families and crew members.