The Weld County Sheriff's Office says the body was found around 10 a.m., and it appears the man was hit by a train. They say it looks like the body had been there for about 12 hours.
Deputies found identification on the man, but the coroner will work to determine if the ID matches the body.
A Colorado State University Spokeswoman says the man was a student at CSU and a member of the Alpha Tau Omega Fraternity.
Investigators say they are working with police in Denver to see if the body matches any missing person reports.
Deputies say they have "no reason to believe" the death was a suicide.
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