A deadly blizzard hit sections of the Southwest and Great Plains Monday dropping up to 18 in. of snow, burying sections of New Mexico, Texas, Oklahoma, Kansas and Colorado under a blanket of heavy snow. Snow and winds up to 45 mph cut visibility to zero in some areas, shutting down highways and causing dozens of highway crashes, according to media reports.

Major highways were shut down from eastern New Mexico to Kansas and nearly 100 rescue calls came in from motorists in the Texas Panhandle as blizzard conditions forced part of Interstate 40, a major east-west route, to close Monday night, according to the Huffington Post. Highways were also shut down across western and southwestern Kansas, including a western section of the I-70, the main thoroughfare that traverses the state due to snowpack and icy conditions.

Highway officials reported that travel on major Interstates throughout the region was risky. In New Mexico, Interstate 25 between Las Vegas and Wagon Mound was closed due to ice and zero visibility. Treacherous snow and ice created problems for drivers on Interstate 35 in Oklahoma, Kansas and Texas, Interstate 40 in New Mexico and Interstate 70 across central Kansas. Motorists were urged to check road conditions before heading out on the highways.

At least six deaths are being blamed on the storm. Authorities said four people were killed when their vehicle collided with a pickup truck in part of eastern New Mexico and a prison guard and inmate died when a prison van crashed along an icy roadway in eastern Colorado.