Investigators say skid marks show a truck driver tried to stop and slid at least 300 feet before crashing into the train Friday morning near Trinity, Nev., which is approximately 70 miles east of Reno. The impact reportedly caused a fire that burned the truck and two train cars.
On Sunday, investigators say the semi was heading up a three-truck convoy, and that the two other drivers were able to stop.
The Amtrak route originated in Chicago and was headed for the San Francisco Bay Area.
The truck involved in the accident belonged to John Davies Trucking of Battle Mountain, Nev. A report released by the Associated Press on Sunday says the company has been cited repeatedly for crashes, unsafe driving and operating a truck with bald tires.
The truck driver, who remained unidentified Sunday, was killed in the accident. The train conductor was also killed, and five people were still unaccounted for Sunday night. Officials say some passengers may have gotten off the train before the accident or were possibly able to leave the scene without informing authorities.
At a press conference late Saturday night, the National Transportation Safety Board laid out its plan to find out the cause behind the accident.
Investigators said they would comb over every aspect of the tractor trailer that slammed into the California Zephyr, including the driver's records. Determining why the truck driver plowed through the crossing, however, may take up to a year.
"On behalf of the NTSB, I'd like to extend our sympathies to the families of the victims of this tragic accident," said NTSB spokesperson Earl Weener. "Our mission here is to understand not just what happened, but why it happened, and to recommend changes to prevent it from happening again."
The NTSB will examine, among other things, whether the tractor trailer that hit that train was functioning properly. Furthermore, they will be looking at the driver's history and training, as well as into toxicology reports.
An initial investigation has found that the signal light and crossing guard arms were working and that there was good visibility of the train tracks from the road.
"We will not be determining the probable cause of this accident while we are here on the scene, nor will we speculate what may have caused the accident. But we expect to be on the scene between seven to 10 days," Weener said.
Police said officials from the coroner's office are still sifting through the rubble of two burned out train cars. A forensic anthropologist is expected to join them to help determine if any more bodies are inside. Investigators say it may take up to a year to determine why the truck driver plowed through the crossing.
Those with questions about their friends and family aboard the train can call 1-800-523-9101 for information.