The mother of a toddler found dead in a car near a Grand County rest area was behind bars Saturday, booked into jail for investigation of murder.

Wendy Bullock, 28, Salt Lake City, was arrested after being treated at Castleview Hospital in Price for unspecified self-inflicted wounds, the Grand County Sheriff's Office reported Saturday.

Possible charges are being screened with the Grand County attorney and could be filed next week, according to the sheriff's office.

Relatives of Bullock declined comment Saturday.

Meanwhile, the body of Bullock's 2 1/2-year-old daughter was transported to the Utah State Medical Examiner's Office, where the cause of her death will be determined, according to sheriff's officials.

The child was found unresponsive in a car seat inside the woman's vehicle.

Friday morning, a motorist stopped on I-70 near Thompson Springs was approached by a woman parked at a nearby rest stop, sheriff's officials said. The woman was injured, and the motorist called for help.

Responding sheriff's officials found a toddler, unresponsive, in the back of the woman's car.

Investigators were releasing few additional details Saturday.

"We're still investigating," detective Steve White said.