A survivor of the deadly Amtrak derailment in the US state of Missouri has given his exclusive first-hand account of how events unfolded on June 27.

At least three people were killed and dozens more are reported injured after when passenger train derailed after hitting a truck.

Dax McDonald was travelling from Flagstaff, Arizona to Fort Madison in Iowa with his two sisters and his mother ahead of July 4th celebrations.

They had been enjoying the journey in the car second from the back when McDonald spotted a cloud of dust ahead and the truck.

"I heard a massive bang in which the entire rail car shook," he told Newsflare in this exclusive interview.

"The car was tipped violently to the right-hand side. I was already on the right-hand side so I didn't have much to fall," he added.

"My sisters both came flying across and they hit the side of the train car," he said.

One of his sisters was uninjured in the fall but another is still being diagnosed with a possible concussion.

McDonald then recounted how he and other passengers climbed out of the left side of the train - which was now above their heads - and descended to the ground.

"It's still unbelievable to talk about it," McDonald said.

McDonald and his family were then taken to a high school in the town of Mendon where they were given drinks and treated for their injuries.

"I'm so grateful for the way the town of Mendon came together," he said.

McDonald said he still didn't know how he's going to get home.

"It was a roundtrip ticket and the concept of riding Amtrak on the way home is pretty daunting," he told Newsflare.

Dax McDonald describes the circumstances of his families travel aboard the train along with a detailed recount of what happened immediately before the accident. He then describes what steps his family took to escape the train and their ensuing treatment at the nearby high school and hospital.