One person died and another was in critical condition Saturday when an RV slammed head-on into a Nissan on State Route 191 in Daggett County, authorities said. The crash occurred before 6 p.m. about 25 miles north of Vernal, and resulted in a temporary closure of the highway, the Utah Highway Patrol and the Utah Department of Transportation reported. The Nissan was traveling south when it crossed the median and struck the RV, which was towing another vehicle, UHP officials said.