A man was arrested Saturday on charges he kidnapped his girlfriend's 8-year-old granddaughter, then raped and killed her, authorities said.

Jessica Rae Delatorre's (search) body was found under some trees on a gravel road near Fulton, about 70 miles west of Sioux Falls, authorities said. Police said the suspect, Murray James Jones, 41, led them to the body.

Jones was expected to be arraigned Monday on charges of first-degree murder, rape and kidnapping, Police Chief Doug Barthel (search) said.

Barthel said Jessica's grandmother had asked Jones to watch Jessica and her two brothers, ages 4 and 11, when she was away Friday night. Jessica lived with her mother in Sioux Falls (search) but was staying with her grandmother.

"It's not uncommon for the children to spend the night at their grandma's, and this was just one of those nights," Barthel said.

Barthel said that while Jessica's brothers were sleeping, Jones kidnapped the girl and drove her to Fulton where he raped and killed her.

The grandmother, who has not been identified, called police Saturday morning after she returned home and found Jessica missing. Investigators discussed issuing an Amber Alert, but focused instead on Jones, Barthel said.

A cause of death had not yet been determined, but Barthel said it did not appear a weapon had been used.