A military veteran who was severely injured in a parade crash in Texas last week recalled chilling screams before an oncoming train plowed into the flatbed truck he was riding, killing four people and injuring others.

Sgt. 1st Class Richard Sanchez, who broke his back in the crash and could be paralyzed, spoke with Matt Lauer from his hospital bed on TODAY Monday about the moments before impact. He was on the second truck in the annual Show of Support parade for military veterans in Midland, Texas, that was hit by a Union Pacific freight train as it crossed the tracks.

“It all kind of happens at once, there’s not really any delay in time, but I remember it all from the first time I heard somebody yelling ‘train!’ to the arm coming down on my wife and I, and then me pushing her and me getting thrown,’’ Sanchez said. “It just all seems to go by extremely fast. My wife and I were kind of already almost past the train tracks, so we were already looking off to start waving to the next group of little kids, but one of the ladies behind us… yelled ‘train!’ And I just happened to look up and saw the crossing arms come down.’’

In a timeline created by the National Transportation Safety Board from information in the train’s black box along with video from the train and a sheriff’s escort car, the warning bells and lights for the train crossing began going off 20 seconds before the impact. Thirteen seconds before the crash, the crossing gates started to come down after the first truckload of veterans crossed the tracks.

With 12 seconds before the crash, the second truck began to cross the tracks. The engineer sounded the train’s horn and then slammed on the emergency brake five seconds before impact, but it was too late.

“I remember the guard coming down, I remember Richard yelling at me to jump, and I remember his hands on my back,’’ Sanchez’s wife, Heather, told Lauer. “The next thing I know I was on the ground, and I saw my husband laying in a ball. I thought he was dead. He wasn’t moving, it didn’t look like he was breathing, (and) there was blood everywhere. He was just crumpled up, so I just started screaming his name, and that’s when he woke up.’’

“I had my back broken down by the L5 (veterbra),’’ Richard said. “I’m just kind of waiting to see if we can get the swelling down by the spinal cord so I can try to walk again.’’

The veterans from the first truck that made it safely across the tracks quickly raced back to help those injured in the crash.

“For many of them, their training kicked in, and as soon as they jumped off that trailer they were able to help tie tourniquets and stop bleeding vessels,’’ Dr. Sudip Bose, a military physician who treated those injured on the scene, told NBC News. “I couldn’t have done it without their help.’’

The NTSB has not publicly identified the driver and plans to interview him on Monday. He did submit a blood sample immediately after the accident. On Tuesday, the NTSB will have a re-enactment of the crash in order to better determine why it occurred.

Sanchez, who had just returned from a deployment in Afghanistan before the parade, plans to pursue legal action for his injuries. Sanchez’s attorney, Bob Pottroff, spoke with Lauer alongside the Sanchezes.

“You start out by knowing that you don’t hold anybody who was on that float responsible,’’ Pottroff said. “This should never have happened, so you kind of look backwards. There’s reasons why this happened.

“One of the reasons is obvious. The 20-second warning time is not a sufficient warning. You only have to go back to Fox River Grove in Illinois in 1995 to know what happens when you have a short warning time. In that instance, a busload of children were hit. The same warning time in this case, and that is not the way that system was designed. I know it was designed for a 30-second warning time. That information is what we hope to bring to light.”

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