National Transportation Safety Board spokesman Mark Rosekind made that announcement Sunday.
Four war veterans were killed during the parade in Midland on Thursday.
Rosekind identified the company that donated the truck as oilfield services company Smith Industries. He said the company is cooperating with investigators.
Investigators have not released the identity of the driver. Rosekind say they expect to interview the driver on Monday.
According to its website, Smith Industries sells and manufactures oilfield service equipment.
Rick B. Smith, Smith Industries' CEO and president, did not immediately respond to phone calls or emails seeking comment.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
A West Texas oilfield services company donated the truck war veterans were riding on when a train plowed into them, killing four people, investigators said Sunday.
National Transportation Safety Board spokesman Mark Rosekind said Midland-based Smith Industries was the owner of the truck that served as a float during a parade in Midland. Four war veterans were killed Thursday when a train struck the truck.
Rosekind said the company was cooperating with investigators, who expect to interview the driver on Monday. The NTSB declined to release the driver's name.
According to its website, Smith Industries sells and manufactures oilfield service equipment. The website says the company provides steel and fiberglass tanks, separators, ladders, walkways and other equipment. The company has been in operation since 2000.
Rick B. Smith, Smith Industries' CEO and president, did not immediately respond to phone calls or emails seeking comment Sunday.
Midland is in Texas' oil-rich Permian basin, a region that has experienced a significant oil boom in recent years.
Investigators say the truck began crossing the train tracks even though warning bells were sounding and lights were flashing. It was the second of two parade floats filled with wounded war veterans. The first float had already cleared the tracks when the accident happened.
The NTSB released a timeline of the accident Saturday, based on information from cameras and data recorders.
The parade was organized by a group called Show of Support-Hunt for Heroes and was an annual event in Midland for nine years. The group brings wounded veterans to Midland each year for three-day weekend that also includes a banquet and
According to the NTSB, the train sounded its horn nine seconds before the crash. The guardrail hit the truck, and then the engineer pulled the emergency brake, trying to bring the train that was traveling at 62 mph to a screeching halt.
Some people tried to jump off the float, witnesses said. Four veterans of Iraq and Afghanistan were killed and 16 more people were injured.
The NTSB said no mechanical problems were found with the cars or the tracks, and the train's maintenance history was clean. Investigators will try to establish on Monday what the engine could have seen as it approached the truck.
Railroads are a vital part of Midland. Three or four railroad tracks lie within city limits. The city is listed as having nearly 114,000 residents, but residents and officials believe the population has risen significantly with the growth of the oil industry.
The veterans were on their way to a banquet in their honor and were being cheered by a flag-waving crowd when the accident happened.
Killed were Marine Chief Warrant Officer 3 Gary Stouffer, 37; Army Sgt. Maj. Lawrence Boivin, 47; Army Sgt. Joshua Michael, 34; and Army Sgt. Maj. William Lubbers, 43.
Two of the injured were still at a Midland hospital Sunday afternoon, one in critical condition and another in stable condition.
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