GREEN RIVER, Emery County — "We’re on the highway. Can you please help us? I’m scared,” a very panicked woman can be heard begging the 911 dispatcher.

As a cause to the deadly crash of a Greyhound bus into a steep wash off I-70 continued to be investigated, a recording of the first 911 call made from one of the 14 passengers was released Wednesday.

The call was made by a very emotional woman who can be heard screaming, crying and praying during her 30-minute call with an Emery County sheriff's dispatcher.

"Me and my husband are stuck, and a bunch of other people. Our bus crashed. My head is hurting. Our bus crashed and my brain hurts,” she cries, followed by screaming, "Help me, please. Help! Help!"

The following audio contains mildly objectionable language and may be disturbing to listeners.

On New Year's Eve, the bus carrying 13 passengers and a driver was traveling from Denver to Las Vegas when it went off the road near the Devil's Canyon view area and flew into a steep wash, coming to rest about 200 feet off the interstate. A UHP spokesman said the crash could have been worse if the bus had rolled. The bus stayed upright despite crashing head-on into a large bank.

Summer Pinzon, 13, of Azusa, California, was killed and 12 others, including the teen's mother, were injured. The bus driver and two passengers were flown by medical helicopters to hospitals in serious condition. All of the other passengers except one suffered "various injuries" and were transported by ambulance to hospitals in Murray, Price and Richfield, according to the Utah Highway Patrol.

Late Wednesday, UHP Sgt. Todd Royce said investigators from the State Bureau of Investigations had narrowed down the cause of the crash to either a medical condition suffered by the driver or the driver was fatigued. Investigators hoped to review surveillance video from the bus as well as examine the data from the bus' computer to determine speed and braking before reaching a final conclusion on the cause.

Royce said all passengers "who are conscious" have been interviewed by the UHP. He did not have a count Wednesday on how many people were still in the hospital or how many were still unconscious, but said the bus driver was one of those people and had not been interviewed.

During her 911 call, the panicked and possibly disoriented woman repeats several times, "My brain hurts really bad" and "I don't want to die, please don't let me die."

The woman tells the dispatcher "I was sleeping and the bus started shaking" while another man can be heard in the background saying, "The driver passed out and we went in a ditch."

"Please, please, please help us," she begged the dispatcher. "I don’t know where we are."

The woman is heard praying to herself several times, saying "You won't let me down like this" and "Thank you, Jesus" while also singing a hymn.

At one point, the woman and her husband can be heard discussing whether they were actually in a dream.

"I can’t wake up. I can’t wake up. I’m in a dream," the woman tells herself.

It took time for emergency dispatchers to figure out where the crash occurred because neither the woman nor any of the other passengers she talked to knew where they were. Some didn't even know that they were in Utah or along I-70. The woman can be heard along with her husband walking along the freeway screaming at passing cars to help. The dispatcher asks her if she can find a mile marker sign anywhere on the road.

Eventually, two truck drivers pulled over and helped the passengers tell dispatchers where the accident occurred.