VERNAL — A 4-year-old girl was seriously injured Thursday in a horseback riding accident in Uintah County, authorities said.

The girl was riding with family members in a roadless area several miles east of state Route 45 between 6000 South and 7500 South when she was thrown from a horse just before 2 p.m., Uintah County Undersheriff John Laursen said.

While she was still on the ground, the horse stepped on the girl at least once, Laursen said.

Members of the sheriff's search and rescue team were called out to help move the girl to an ambulance, Laursen said. She was ultimately flown by helicopter to Primary Children's Hospital where she was being treated for possible fractures of her collarbone, jaw and pelvis, according to the undersheriff.

Deputies are not investigating the incident, which Laursen described as "strictly accidental." The girl is expected to survive, he said.