SPARKS, Nev. (CBS) — Authorities on Monday released the names of three more victims in last week’s fiery collision between a gravel truck and an Amtrak train in Nevada, and five passengers were still unaccounted for.

Federal investigators say the truck that hit the California Zephyr that originated in Chicago was part of a three-truck convoy. The second and third drivers saw the train, and they stopped, but could only watch as the first truck hit the train.

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There are six confirmed victims, but likely there are more. On Monday, the Nevada Highway Patrol identified the trucker as Lawrence R. Valli, 43, of Winnemuca, Nev.

The NHP also released the names of two passengers who were killed — 58-year-old Francis Knox and her 18-year-old daughter, Karly Knox, of Seward, Neb. — as investigators continued to try to identify other victims from the crash. A 68-year-old train conductor from California previously had been identified as one of the dead.

About 20 people were injured and hospitalized immediately after the crash, and later several others who were initially taken to a local elementary school were transported to local hospitals to be checked out as a precaution.

The rest of the passengers were taken to local schools for shelter and food while arrangements were made to continue to their travel west on chartered motor coaches, the statement said.

The train had 204 passengers and 14 crew aboard, according to the statement.

The National Transportation Safety Board says at the time of the crash, visibility was good, and the crossing gates and warning lights were working.

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Among other factors, investigators plan to look into the trucking company involved in the incident, John Davis Trucking of Battle Mountain, Nev.

The NTSB says the company had seven violations since September of last year.

Investigators want to know if cell phone use was a possible distraction in the Friday accident.

The Associated Press reports the company was cited for two crashes in the past two years, and in January, inspectors found tires on one truck that were severely worn out and considered a hazard.

The NTSB plans to visit the company Tuesday. Investigators say they don’t expect to determine a final cause for the crash for a year.

Contributing: The Sun-Times Media Wire, Associated Press

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