Updated

An Amtrak Auto Train rolled out of a central Florida station Tuesday en route to Washington, returning to the rails for the first time since a derailment five days ago killed four and injured more than 150.

At least six passengers from the derailed train were aboard Tuesday's northbound run.

The National Transportation Safety Board is focusing on a misaligned track as the possible cause of Thursday's derailment near Crescent City.

Amtrak spokesman Howard Reiss said 21 passengers and one crew member from the wrecked train remained hospitalized Tuesday. About half are due for release within a day or two, he said.

Tuesday's train had 363 ticketed passengers, 24 crew members and 192 vehicles, said Sharon Mahoney, the Auto Train's general manager.

Leo Eisenstein, 80, who suffered bruises when he was thrown around in his car as it left the rails last week, admitted to being a little nervous Tuesday.

But his live-in girlfriend, 79-year-old Fay Willner, insisted that they take the train home to New York City.

"Chances are it won't happen twice in a row," Eisenstein said.