PHILADELPHIA (AP) -- Federal investigators say they're still trying to determine whether an Amtrak engineer used his cellphone at the controls of the train in a deadly derailment in Philadelphia.

Brandon Bostian (Huy Richard Mach/St. Louis Post-Dispatch via AP)

The National Transportation Safety Board said Wednesday records show calls were made, texts were sent and data was used on Brandon Bostian's phone the day of the crash.

They say they're comparing the timing of the phone activity with data from the locomotive's event recorder and outward facing video, radio communications and surveillance video.

Bostian's lawyer says he kept the phone in a bag, using it only to call 911 afterward.

The May 12 derailment killed 8 people and injured more than 200. Investigators are looking into why the Washington-to-New York train was going double the 50 mph limit around a sharp curve.

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