Authorities  were trying to determine Thursday whether a man struck by a train in northwest Atlanta was already dead before being hit.

Homicide detectives were called to the CSX tracks off Marietta Boulevard near the Fulton County Jail around midnight Wednesday "just in case there was any foul play," Atlanta police Capt. Adam Lee III told Channel 2 Action News.

The freight train's engineer told police he saw the 55-year-old man lying on the tracks but was unable to stop before  hitting him.

"The engineer of the train advised us that he blew the horn very loudly, and the person didn't move," Lee said. "Unfortunately, trains can't stop on a dime."

The Fulton County Medical Examiner's office was trying to determine the cause of death.

The man's name has not been released.