A railcar carrying bulk corn has derailed in the northern suburbs of Mexico City, rolled over and crushed part of a house by the side of the tracks, killing five people.

The victims were apparently crushed as they slept before dawn Thursday.

The Transportation Department says the train was operated under a private rail concession with Kansas City Southern de Mexico.

The department says the cause of the derailment is under investigation. The company has not commented.

Photos of the scene show the railcar's wheel-truck broken loose, rails separated from ties and the car resting on its side after partly falling down an embankment onto the house.