Updated

The track where an Amtrak Auto Train derailed in a deadly mess of mangled cars and rails was cleared Sunday, allowing the first trains to pass through this northern Florida town since the accident.

The original tracks were torn out in Thursday's derailment, which left four people dead and more than 150 injured. The first coal train that moved through Sunday morning was on temporary rails, said Gary Sease, spokesman for CSX, the freight railroad that owns the track.

The sections of temporary track are each 39 feet long and for now can hold slow-moving trains at 10 mph. The company plans to make improvements this week to allow the temporary tracks to withstand faster trains. He said an average of 28 trains a day are normally scheduled there.

As the coal train passed, workers continued clearing downed trees and debris from the area around the tracks with bulldozers and cranes.

The Auto Train had been headed for Washington with 418 passengers and 34 crew members, as well as 200 automobiles stacked in 23 specially designed cars, when it derailed Thursday.

Its two engines and first two cars stayed on the tracks, but more than half its 40 cars went off, throwing passengers to the cars' floors and against walls.

The lead engineer told the National Transportation Safety Board that he saw a disjointed track about an hour into a trip from Sanford to Lorton, Va., and slammed on the engine's brake. Seconds later, a backup engineer in the locomotive cab and a conductor two cars back felt the train hit disjointed track and switched on emergency brakes as well, NTSB board member George Black said.

The NTSB hasn't said if its investigators have been able to verify if the track was misaligned. The lead engineer said the tracks were misaligned by about 10 inches, NTSB investigator Russ Quimby said.

The area where the crash occurred had chronic problems with water drainage that may have contributed to the accident, Black said. A culvert runs under the tracks that has often waterlogged the sandy soil.

Passing trains can compress the water below the track, forming soft spots and depressing the track downward. Black said the track appeared to be moving under the weight of trains, loosening the bond between crossties, steel tie plates and spikes.

Quimby said later Saturday that the area where the culvert could have caused soft spots was hundreds of feet in front of where the accident occurred.

CSX spokeswoman Jane Covington said she could not comment on the engineer's account of the track being misaligned or on whether CSX maintenance crews had reported problems on the stretch of track, citing the NTSB's ongoing investigation.

Amtrak officials hoped to have the Auto Train running again by Monday or Tuesday, Cantillon said.

The derailment was Amtrak's deadliest accident since March 15, 1999, when a train collided with a truck and derailed near Bourbonnais, Ill., killing 13 people and injuring more than 100.

The last Auto Train accident was in 1998, when a train hit an empty car at a crossing in the Virginia town of Jarratt. There were no injuries.