Northbound and southbound lanes of I-15 in Utah County were closed for several hours Saturday morning after an accident claimed two lives.

Another fatal accident Saturday afternoon put the day's I-15 death toll at three.

Teresa Valencia, 36, was driving northbound on I-15 with her husband, their two sons and three friends in a sport-utility vehicle when the vehicle drifted off the road about 7:20 a.m., said Sgt. Ted Tingey of the Utah Highway Patrol.

Valencia overcorrected and rolled the vehicle. One teenage boy was ejected. The SUV then hit the concrete barrier on the middle of the highway and flipped over onto its roof and into I-15 southbound lanes, and two other male teens were ejected.

Valencia and her son, Kevin Santos, were pronounced dead at the scene. Another teenager was taken to Utah Valley Regional Medical Center and then transported by helicopter to Primary Children's Medical Center, where he was listed in critical condition. A third teenager also was taken to Utah Valley, where he was listed in serious condition. The three other passengers were treated for minor injuries on the scene.

All are expected to survive, Tingey said.

Authorities are still trying to determine the cause of the accident but believe it was related either to distracted driving or a mechanical failure, Tingey said.

Officers were delayed in their initial investigation because the occupants of the vehicle were Hispanic, and none of the first responders spoke Spanish fluently, Tingey said.

The investigation into the accident was further delayed after two Utah Highway Patrol cars and a third vehicle were involved in a separate accident as the troopers left the scene of the fatal accident.

The troopers' accident occurred late Saturday morning on the 500 East overpass above I-15 in Pleasant Grove when Sgt. Corey Nye failed to notice the UHP vehicle he was following in a westbound lane had stopped, Tingey said.

"The trooper was not paying attention," Tingey said, and rear-ended the UHP vehicle ahead of him. That vehicle was then pushed into another car. No one was injured, he said, although one of the trooper's cars had to be towed.

"This is kind of an embarrassing one," Tingey said. The troopers' accident will be investigated by the American Fork Police Department, he said, and Nye could be disciplined, possibly by being sent back to driver training.

All but one lane of traffic in each direction on I-15 were closed for several hours Saturday at mile marker 266 in Utah County. The Highway Patrol reopened the freeway about 11:30 a.m.

Almost five hours later, a California woman died during a similar rollover on the interstate near Beaver. Karen Kooyman was ejected from the back seat when the driver overcorrected and the vehicle rolled, said county dispatchers. She died at the scene.

Another passenger and the car's driver were taken by ambulance to a local hospital and are expected to be OK.

Contributing: Rebecca Palmer

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