CIMARRON, Kan. — Investigators looking into the derailment of an Amtrak passenger train in southwest Kansas plan to review rail conditions and other factors as they seek to determine the cause of the accident, a federal transportation official said.

Amtrak’s Southwest Chief was carrying more than 140 people when several rail cars derailed early Monday, moments after an engineer noticed a significant bend in a rail and applied the emergency brakes, authorities said. At least 32 people were hurt, two of them critically.

Local authorities said they were checking whether a vehicle crash may have damaged the track before the accident.

National Transportation Safety Board member Earl Weener said Monday at a news conference that investigators would review data from cameras and recorders on the train as well as the condition of the rails and crew performance. He put the train’s speed at the normal limit of 60 mph.

Weener said there was some initial indication of a “misalignment” on the rail, but it was unclear what that was or what caused it. He said the engineer was vigilant and noticed the variation on the track, causing him to brake. The track was inspected last week, Weener said.

The train, which had about 130 passengers and 14 crew members, was making a 43-hour journey from Los Angeles to Chicago when it derailed shortly after midnight along a straight stretch of tracks in flat farmland near Cimarron, a small community about 160 miles west of Wichita. Eight cars derailed, and four of them ended up on their sides.

Thirty-two people were taken to hospitals for treatment. Four of them remained hospitalized Monday night, including two people who were airlifted to Amarillo, Texas.