Slick roads from an overnight snowstorm contributed to crashes Thursday morning in Montezuma County.

About 8:30 a.m. a southbound semitrailer on U.S. 491 crashed off the road near Pleasant View, rolled down steep embankment and landed on its roof, said Master Trooper Gary Cutler of the Colorado State Patrol.

Rescue crews extricated the driver, who was seriously injured, he said. The man was flown by helicopter to San Juan Medical Center in Farmington.

The crash was weather related, said Montezuma County Sheriff Steve Nowlin. He said the driver was pinned inside the cab after the trailer separated from the tractor. A hazmat team from Colorado Department of Transportation cleaned up spilled materials.

U.S. Highway 491, temporally closed after the crash, reopened at 10:18 a.m., according to Montezuma County Emergency Alert system.

About 3 a.m., a semitrailer slid off U.S. 491 in the same area, struck a fence and had to be towed, Cutler said. There were no injuries.

Nowlin reported multiple slide-offs on county roads and on U.S. Highway 160 Thursday morning. There were no reported serious injuries.

Road were mostly clear and dry Thursday afternoon in lower elevations, Nowlin said.

Colorado State Patrol Capt. John Trentini also reported multiple crashes in La Plata County Thursday morning, including on U.S. Highway 160 east of Bayfield.

Crashes in icy conditions are usually a result of driving too fast for conditions, he said.