Nov. 16, 2012 -- Police have identified the four servicemen who died in Midland, Texas when a freight train plowed into a parade float carrying wounded veterans and their spouses at a crossing, two of whom saved their wives by pushing them to safety before they died.

Army Sgt. Maj. Gary Stouffer, 37, and 47-year-old Army Sgt. Maj. Lawrence Boivin were pronounced dead at the scene, police said, after the float carrying wounded veterans and their families to an honorary banquet was struck by a Union Pacific train around 4:30 p.m. Thursday afternoon. The train struck as the parade was crossing the tracks, turning the honorary event into a scene of destruction.

Army Sgt. Joshua Michael, 34, and 43-year-old Army Sgt. Maj. William Lubbers were transported from the scene and later pronounced dead at Midland Memorial Hospital, according to the Midland Police.

Seventeen people in all were transported to the hospital and 10 were treated and released. Four people were in stable condition and one is in critical condition as of this morning.

Michael was killed in the crash but was able to save his wife, his mother-in-law told the Amarillo Globe-News.

"He pushed his wife off the float -- my daughter," Mary Hefley told the newspaper. "He was that kind of guy. He always had a smile on his face. He would do for others before he would do for himself."

Hefley said Michael retired from the Army due to health reasons.

According to a website set up by Cory Rogers, a friend of Michael's family, the father of two completed two tours of duty in Iraq, and received two Purple Hearts after being wounded in combat.

"His love of country and for his wife, Daylyn and their two children shone through," his family said in a statement on the site. "The family appreciates everyone's thoughts and prayers in this very difficult time."

Sgt. Maj. Boivin also pushed his wife out of the way before he was hit, Jaime Garza told ABC News. He said that his wife was hurt in the crash, but survived. Boivin died in his arms, Garza said.

Garza said that he and his wife Denise lost their son in Afghanistan seven years ago. On Thursday, they were driving in a separate car about a block away, helping escort the floats.

"I looked in my rear view mirror. That's when I saw the train hit the float," he said. "I made a quick U-turn to get back up there. The first person who was there was Lawrence. I had to help him out ... and he gave me his last breath ... He actually pushed [his wife] off the float and then he got hit."

Denise Garza said that the entire incident happened very fast.

"Everybody was getting help in two seconds. Everybody had help. It was like the best response," she said. "It was terrible. The worst thing I've ever seen in my whole life."

About two dozen veterans and their spouses had been sitting in chairs on the back of a flatbed tractor-trailer decorated with American flags and signs identifying each veteran.

The first truck crossed the tracks in time, but the second did not, according to Hamid Vatankhah, a witness who owns a used car lot near the scene of the crash.

Sirens from the police cars in the parade may have drowned out the sound of the approaching train, Vatankhah said.

The impact, witnesses say, was deafening as the train plowed through the parade float crossing the tracks in an industrial part of Midland.

"Some people were able to jump, and some that were sitting in wheelchairs on top couldn't do nothing about it," Vatankhah said.

Patricia Howle was sitting traffic with her daughter watching the parade go by when she heard the train honking its horn.

"I just saw people going under the train," said eyewitness Eservando Wisler. "There was blood. There was blood all over."

A Union Pacific spokesman, Tom Lange, said it appeared safety devices at the crash site were working. But there were conflicting reports by eyewitnesses about whether the gates went down at the crossing when the train approached.

"I saw the truck crossing the tracks. About halfway across the gates started coming down. The truck tried to blow his horn to get the other people in front of him out of the way. The gates actually hit the first people on the trailer," witness Michael Briggs said.

"Our preliminary findings indicate that the lights and gates were working at the time of the incident and that our train crew sounded the locomotive horn," said Lange.

Midland, Texas, Train-Parade Crash Under Investigation

The National Transportation Safety Board was at the scene and has launched an investigation into the accident.

This evening, an NTSB official said video recorders from the train were on their way to Washington for analysis by the board.

He added that there have been prior accidents at the scene of Thursday's disaster.

"There were some accidents from 1979 to 1997 but there has not been an accident at this train crossing in the last 15 years, so the question is what might have changed in that period of time," said the official, Mark Rosekind.

The Texas Department of Transportation told ABC News that the state has actually seen vehicle and train-related fatalities decline 68 percent the last 10 years.

Regarding Thursday's accident, NTSB investigators should be able to determine the speed of the train, as well as whether the train's horn was sounded prior to the accident, when they examine the train's black box.

Rosekind said the NTSB also will be able to study the circumstances of the accident in other ways.

"Our investigators are looking at the rules, regulations, requirements, permits, related to the parade," Rosekind said. "Specifically, we're going to be looking at what the requirements are in notifying the railroad and whether all the procedures, permits, etc., were actually followed, by everyone.

"Our mission is to determine the probable cause, which is determining not just what happened but why," he said, "and that why is critical for us to determine what safety recommendations need to be issued so this does not happen again."

Secretary of Defense Leon Panetta "was deeply saddened by news of the tragic accident involving veteran heroes and their spouses in Midland," Pentagon spokesman George Little said in a statement. "His thoughts and prayers are with the families of the victims, with those injured in this incident, and with the entire community."

"It's obviously a real sad day for Midland, Texas. This may be one of the most tragic events we've had in our town," Mayor Wes Perry said.

Perry today hosted a community-wide prayer vigil to help show support for the victims and their families that have been affected by the incident at the Centennial Plaza in Downtown Midland. Mayor Perry is asking citizens to show support by lowering their flags to half-mast until Monday morning at 8 a.m.

ABC News' Michael S. James and Steven Portnoy contributed to this report.