(CNN) -- Federal authorities say they are trying to account for passengers missing from an Amtrak train that was struck by a tractor-trailer truck east of Reno, Nevada.
There have been conflicting casualty reports since the truck slammed into the Chicago-to-California passenger train Friday at a railroad crossing near Lovelock, Nevada, and burst into flames. The fire, investigators say, burned the truck and two train cars.
At least two people -- one on the train, one in the truck -- were killed, Nevada Highway Patrol Trooper Dan Lopez said early Saturday, the same figure he provided shortly after the crash. Some reports, though, have put the number as high as seven people dead.
The National Transportation Safety Board, which is investigating, has referred requests regarding casualties to the Churchill Country coroner's office. The coroner's office declined to release the information, saying figures were not available.
Earl Weener, an NTSB board member, hinted during a news conference late Saturday that part of the problem may be because investigators were trying to account for passengers who had gotten off the train earlier or bought a ticket but did not take the train.
"There are a number of reasons that the manifest and that number don't jibe," Earl Weener told reporters during a news conference late Saturday night in Sparks, Nevada.
The 10-car train, which was on its way to Emeryville, California, was carrying 204 passengers and 14 crew members, Amtrak said in a statement released Friday.
It was not immediately clear how many people were injured. Amtrak said that numerous people aboard the train had been taken to area hospitals for treatment.
Amateur video taken after the crash showed huge plumes of black smoke billowing from the train as a fire burned. Passengers and crew members stood outside.
One voice on the video can be heard telling people to get away from the smoke. Another tells a woman, out of view, to "hang and jump." A third voice asks someone, "Are you OK?"
"Next thing I know, we get hit by something. A big ball of fire comes in. I jumped out the window," passenger Justin Rhine told CNN affiliate KOLO-TV in Reno. "I saw people flying on the other side of the train."
Skid marks show the driver of the truck slammed on his brakes, sliding more than 300 feet before hitting the train, Weener said.
The initial investigation found the signal light and crossing guard arms were working, and that there was good visibility of the train tracks from the road, he said.
The truck was the lead in a three-truck convoy as it approached the train tracks, Weener said.
The two following saw the train signal and slowed to stop, "waiting for him to come to stop," he said.
Though the driver of the truck has not been identified, Weener said the truck belonged to John Davies Trucking of Battle Mountain, Nevada.
The trucking company, which advertises itself as family-owned business that hauls concrete, did not immediately respond to a CNN request for comment.
(via CNN)