Police are searching for a half-dozen people who survived a crash on I-15, then fled after a teenage girl was killed.

The accident happened about 5:30 a.m. Wednesday near the Iron County town of Paragonah.

Utah Highway Patrol trooper Cameron Roden said a minivan carrying between six and eight passengers was headed north on I-15 when the driver apparently fell asleep. The vehicle drifted into the median, at which point the driver overcorrected back onto the road.

The minivan rolled two times, coming to rest in the middle of the road, facing east, Roden said. Two witnesses stopped to assist the of the van, he said, but when one of the witnesses started calling 911, all but two of the occupants ran into nearby fields.

A female in the driver's seat and a female on the passenger side of the middle seat were still in the van and were trying to move it when they saw a semitrailer truck approaching. Roden said the witnesses ran into the median to avoid getting hit, and the semi hit the passenger side of the van, ejecting the female passenger onto the road and killing her.

"She received severe head trauma," Roden said Wednesday afternoon.

Late Wednesday, police identified the girl who died as 16-year-old Brenda Veronica Martinez, of El Salvador. She had been living in Los Angeles and may have been headed toward Denver, Roden said.

The impact of the crash forced the minivan into one of the witnesses' cars, Roden said. The semi went off the east side of the road and through two fences, coming to rest in a field. The driver of the semi was taken to a hospital with minor injuries.

Authorities said it is possible the people inside the van are illegal immigrants. None but Martinez had been found or identified by Wednesday night. The vehicle was registered out of California, and troopers said they found receipts of wire transfers to El Salvador and other evidence that leads them to suspect they may be immigrants being transported elsewhere.

The Iron County Sheriff's Office said it was still trying to track down those who were involved in the crash, to see if they are injured.

Contributing: Greg Kratz

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