Four people were killed Tuesday in traffic accidents on Utah roads, the Utah Highway Patrol said.

Killed:Dana Marie Hart, 22, Arvada, Colo.

Kevork Orangian, 31, Broomfield, Colo.

Harold McCombs, 45, Hyrum, Cache County

Dennis Merritt, 27, Hyrum, Cache County

McCombs and Merritt were killed in a head-on collision on U.S. 91 in Sardine Canyon, 12 miles east of Brigham City, a dispatcher said.

Merritt was in the westbound lanes when McCombs' vehicle drifted across the highway and into the opposite lanes, the UHP said. Both men were killed on impact in the 3:50 p.m. accident.

The two Colorado residents were killed in a 6 a.m. rollover on I-70 near the Utah-Colorado line, the patrol said. Hart and passenger Orangian were dead at the scene, about 10 miles east of Cisco, Grand County.

The vehicle veered from the road twice and rolled, ejecting both occupants, troopers said. The driver may have fallen asleep at the wheel.