Amtrak is investigating after unidentified objects broke a train window and frightened passengers bound for New York.  It happened around seven last night, as the train rolled through Pennsylvania, enroute from DC to New York.  Sleeping passengers were jolted awake by what some told CBS 2 News sounded like a gunshot. 

No one was hurt, but police confirmed that objects were hurled at the train and are trying to figure out what. The incident comes as the NTSB prepares to release information today about last May's deadly Amtrak crash that killed eight people in Philadelphia. In that case, a dispatcher said the train had been shot at or hit by a rock.