JEFFERSON COUNTY, Colo. (CBS4) – A deadly crash on Interstate 70 heading west closed some lanes Sunday afternoon. Colorado Department of Transportation says the crash happened between the Chief Hosa and Evergreen Parkway exits.

(credit: CDOT)

Colorado State Patrol says a 47-year-old male motorcyclist died and only one vehicle was involved. Investigators believe speed was a factor, saying specifically the motorcyclist was traveling through a curve and drifted into the outside guardrail.

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CSP says 911 callers reported seeing a group of motorcyclists speeding, swerving and cutting drivers off before the crash.

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There were miles of traffic backup. Right lanes were blocked.

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“Curiosity slowing impacting eastbound traffic. Please be mindful of traffic conditions ahead of you,” CSP said on social media.

Danielle Chavira