Struck by what?
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The Amtrak train that derailed Tuesday, killing eight people and injuring more than 200, may have been struck by an object before it careened off the tracks, an assistant conductor on the train told investigators from the National Transportation Safety Board.

At a news conference on Friday, Robert L. Sumwalt, the safety board official who is leading the investigation, said an assistant conductor had reported that she believed she heard a radio transmission in which an engineer on a regional line said his train had been struck by a projectile and the engineer on the Amtrak train replied that his had been struck, too.