MORRISON, Colo. -- A slow vehicle caused a chain reaction crash that resulted in four wrecks and at least one injury on Saturday afternoon on Interstate 70 near Morrison.

Colorado State Patrol spokesman Ryan Sullivan said a vehicle either stalled or was moving much slower than the rest of traffic on the highway at around 1 p.m. at milemarker 257. That vehicles was rear-ended by another vehicle. Sullivan said that began a chain reaction of rear-ending that netted four vehicles.

The area where the accident happened is a steep incline out of the Denver metro area into the mountains, located 2 miles west of the C-470 junction. CSP had all lanes of westbound I-70 closed for an hour until the accident could be cleared.