A 10-year-old Eagle Mountain boy died Thursday afternoon after the 4-wheeler he was riding with his baby sitter rolled off a 22-foot cliff.

Tooele County sheriff’s Sgt. Ron Johnson said the boy was riding behind his 31-year-old female baby sitter at the Five Mile Pass Recreation Area, on the border of Tooele and Utah counties.

He said the pair rode up a steep embankment when the ATV either cut out or died and rolled backward off the cliff. When emergency personnel arrived, they found the pair lying to the right of the ATV.

“It appears they could have landed on rock,” Johnson said.

The boy was pronounced dead, and the 31-year-old, also of Eagle Mountain, was flown by medical helicopter to University Hospital in Salt Lake City, Johnson said. Her condition was not immediately available.

The boy’s name was being withheld until his family could be notified.