A man who was walking on railroad tracks in a remote area of Springfield was fatally struck by an Amtrak train Thursday night in an incident that delayed train service for hundreds of commuters, Fairfax County police and train officials said.

Amtrak’s No. 19 Crescent hit the man as it traveled on the Norfolk Southern tracks near Backlick and Wimsatt roads about 7 p.m.

The man, whom authorities had not identified, was dead at the scene. It was not immediately clear why he was on the tracks, said Officer Shelley Broderick, a police spokeswoman.

The New Orleans-bound train, with 226 passengers, was delayed in Springfield for hours as authorities cleared the scene and investigated, said Steve Kulm, an Amtrak spokesman.

The accident forced Virginia Railway Express officials to stop the final commuter train of the evening at the Backlick station and find buses for more than 200 passengers, said Mark Roeber, a VRE spokesman.

It took about 90 minutes for officials to load those buses and deliver passengers to their stations, officials said.