05/17/2015 11:39 am ET Updated May 17, 2015

Lead Investigator Of Amtrak Crash Downplays Theory That Train Was Shot At

National Transit Safety Board lead engineer Robert Sumwalt on Sunday added detail to reports that the Amtrak train that derailed last week had been struck by an object prior to the deadly crash, but he rejected the theory that the train had been shot at.

Eight people died and more than 200 people were injured Tuesday when a Northeast Regional Train 188 jumped the track as it traveled more than twice the speed limit. Brandon Bostian, the train's engineer, has said through his lawyer that he doesn't remember anything prior to the crash.

An unnamed conductor on the train told investigators that she remembered hearing Bostian "say something about his train being struck by something" to a different train's engineer over the radio, ABC News reported. On Friday, the safety board said the FBI would examine the train's windshield and front end to determine if it had been hit by some sort of projectile, to see whether there is a connection between three different trains that may have all been hit by objects, just a few miles apart, on the night of the derailment.

But Sumwalt said Bostian never communicated any news of a projectile hitting the train.

"This idea of something striking the train, that’s one of the many things we are looking at right now," Sumwalt told George Stephanopoulos on ABC's "This Week" Sunday. "We interviewed the Amtrak – well, let’s see, we interviewed the dispatchers and we listened to the dispatch tape, and we heard no communications at all from the Amtrak engineer to the dispatch center to say that something had struck his train."

"Nothing at all?" Stephanopolous asked.

"Nothing at all that he reported to the dispatch center," Sumwalt said.

On CBS News' "Face the Nation," Sumwalt told host Bob Schieffer that it didn't look like someone had shot at the train, though he didn't reject the theory that an object had hit the train.

"I'd like to downplay that part, seeing the fracture pattern, it look like something the size of a grapefruit, if you will, and it did not even penetrate the windshield," he said.

Sumwalt also said that though investigators remain "in the fact finding stage of the investigation," they can make some conclusions about measures that would have helped in the incident.

"I will say this, that we’ve called for inward-facing video cameras for a long time, and we feel that had we had cameras, that would have helped with this investigation significantly," he told Stephanopolous.



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