Road accidents claimed four lives in Utah over the past three days.

Joseph Salazar, 19, West Valley City, died Thursday morning when his speeding car sideswiped another vehicle on state Route 201 near I-215 and rolled, ejecting him, said Utah Highway Patrol trooper Cameron Roden.

Roden said it appeared Salazar attempted to turn onto I-215 but changed his mind at the last second. The car was traveling about 100 mph. A female passenger in the car told investigators that she and Salazar were arguing just prior to the 12:13 a.m. crash. The woman was transported to a local hospital with non-life threatening injuries.

A fiery crash Thursday on state Route 36 in Tooele County killed Thomas E. Snyder, 36.

Snyder was driving south about 1:23 p.m. when his car collided with a semitrailer truck, Roden said.

"The driver of the semi stated that as he watched the Malibu coming towards him, it looked like the driver was leaning over into the passenger seat and started to drift over in the northbound lanes," Roden said.

The semi tried to move but was clipped by the car which spun out and caught fire, Roden said.

St. George police are investigating a motorcycle crash that killed a Washington City man when a flatbed trailer separated from a truck on River Road, Sgt. James Van Fleet said Thursday.

"A car was able to get out of the way, but a motorcyclist was not," Van Fleet said.

David Livings, 54, was taken to Dixie Regional Medical Center and later flown to a Las Vegas hospital, where police said he died.

A Sandy woman was killed at the corner of 3800 South and California Avenue (1330 South) after her car was struck by oncoming traffic as she pulled into the intersection.

Police believe Tammy Lynn Bench was trying to make room for a semitractor to turn, said Salt Lake City Police Lt. Lamar Yule.

Her car was hit broadside by a westbound pickup truck and her small sports car was pushed across the intersection into a large ditch, Yule said.

Bench died before a medical helicopter arrived.

The woman driving the pickup truck was shaken up but not physically injured, Yule said.