Passenger on derailed Amtrak train says 'everything was in slow motion' Scott Claggett said he'd been excited to ride the train for the first time.

 -- A passenger on the Amtrak train that derailed as it traveled over an overpass near Tacoma, Washington, said initially he thought nothing of the train leaning first to the left and then to the right as it moved.

"I fly a lot, and we have a lot of turbulence," Scott Claggett told ABC News' David Muir today. "I realized once the windows started shattering and people started flying, that this was a crash."

Claggett was among the at least 84 passengers and crew members aboard the Amtrak Cascades train 501 as it took its inaugural run down a new route today. The train was also carrying seven crew members, Amtrak said. At least three people died and dozens were injured in the accident.

Claggett told Muir he was traveling to Portland for a business meeting.

"I was completely pumped up and stoked and just really excited for the day ahead," he said.

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He said that once the derailment occurred, everything appeared to happen in slow motion.

"People were flying in the air. ... As that was happening, I just crawled into a ball and was just waiting and hoping and praying the train would stop," he said.

Once the train stopped, he said it was pitch black inside the cars. He told Muir that he pulled up the flashlight on his cellphone to see if he could help others around him.

"Some were unresponsive, and some were responsive," Claggett said.

He said that he was able to get out of the train through a window. When he got out, he found that his train car was in a wooded area and that it was about one and a half stories above the ground. He said he could still hear screams of people in the train's cars.

"Once I jumped out of the train, I realized how high I was and I landed on the ground, still hearing screams," Claggett said. "There's nothing more that I can do, which is pretty painful to want to help somebody but you can't because I am so far below ... There were people in need."