An Amtrak train derailed in southwest Kansas early Monday, March 14, 2016, injuring multiple people who were transferred to hospitals in Garden City and Dodge City, according to a release from Amtrak. The Amtrak train carrying 131 passengers derailed in rural Kansas moments after an engineer noticed a significant bend in a rail and applied the emergency brakes, an official said. (Oliver Morrison /The Wichita Eagle via AP)

CIMARRON — Federal authorities say a preliminary investigation shows that an Amtrak train derailed last month in Kansas in an area where damage to the track was traced to a grain truck.

The National Transportation Safety Board said Thursday that Amtrak and BNSF Railway estimate damages at more than $1.4 million.

The passenger train traveling from Los Angeles to Chicago was carrying 130 passengers and 14 crew members when it derailed March 14 near Cimarron, injuring 28 passengers.

Four derailed cars fell on their sides, while two others remained upright.

Investigators found fresh tire tracks at the site of bent tracks, along with flaked corn typically used to feed cattle. The tracks were traced to a feedlot owned by Cimarron Crossing Feeders, where they matched the treads on a feed truck.