The Utah Highway Patrol says 73-year-old Karen Wells and 74-year-old Floyd Wells of Queen Creek, Ariz., died in the crash about 4:30 p.m. Wednesday.
The driver of the semi-truck told authorities he heard a noise in his vehicle and stopped in the emergency lane on Interstate 15 in western Utah's Millard County.
Troopers say the Camry left its lane and slammed into the back of the truck. The two people inside died on impact.
Authorities say there were no signs of braking before the crash. Investigators don't suspect alcohol or drugs were a factor.
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