The Colorado State Patrol says the Freightliner semi truck was heading northbound on Highway 71 near Last Chance when the driver lost control.
It happened around 8:15 a.m.
The driver, 36-year-old William Gregory of Bridgeport, Neb., was not wearing a seatbelt, according to troopers. He was pronounced dead on the scene by the Washington County coroner.
The passenger, 30-year-old Barrett Hornberger, also of Bridgeport, was also not wearing a seatbelt and was pronounced dead at the scene.
The incident is still under investigation and troopers say they believe speed was a factor in the crash.
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