(NBC News) Investigators are placing more focus on the engineer at the controls in the New York commuter train accident that left four people dead and 63 injured.
The executive director of the Rail Employees Union now says 46-year-old engineer William Rockefeller, who was injured in crash, has said he caught himself "nodding off" at the controls.
Rockefeller told police he "zoned out" and doesn't remember any of the events just before the metro north commuter train left the tracks.
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