Jerrod Metsker, 24, was the last person seen with the girl at the trailer park where both lived, a sheriff's investigator said.
He was arrested Sunday, about 12 hours after deputies found Reann Murphy's body. A judge Monday ordered that he be held in jail on a $1 million bond.
Investigators with the Wayne County Sheriff's office described Metsker as a family friend and neighbor.
Relatives said Reann and her mother had just moved into the trailer park a few months ago around the beginning of the school year. They lived in an apartment above a maintenance garage at the park outside Smithville, about 30 miles southwest of Akron.
The girl's mother was at work Saturday afternoon while Reann was at home with her mother's live-in boyfriend, said sheriff's Capt. Douglas Hunter.
She went outside to play in the snow and was with several other children in the trailer park's courtyard, but the others went home, leaving Metsker alone with the girl, Hunter said.
Reann was reported missing Saturday evening, about two hours after she was last seen with Metsker, Hunter said.
Officers, firefighters and neighbors went door to door looking for her before Reann's body was found in the trash bin five hours after she was reported missing.
Authorities spoke with Metsker soon after at the trailer home he shared with his mother, but he was not arrested until Sunday afternoon, Hunter said.
A county public defender was appointed to represent Metsker, who is unemployed. A woman who answered a phone listed for him hung up on Monday.
Metsker appeared for his arraignment Monday before a Wayne County municipal court judge via video from jail. A preliminary hearing was scheduled for Dec. 23. County prosecutor Daniel Lutz said the case could go to a grand jury on Friday if the evidence is processed in time.
Authorities have not offered a possible motive for her killing. Lutz said a coroner will determine the cause of death but that the girl was not shot or stabbed.
"The charges that we ultimately bring will clarify what we think the motive was," Lutz told The Associated Press on Monday.
Relatives said Reann lived with her mother but also spent time with her father and his family. They said that she loved to play outside and described her as a tomboy.
"She was a little firecracker, always ready to wrestle and play," said Paula Watts, the girl's cousin. "She wasn't into girlie stuff. Last Christmas, she said she wanted some girlie stuff. I don't know if she ever wore the makeup we got her."
Reann was supposed to stay at her home Saturday night, but her mother never dropped her off before going to work, Watts said.
"She was one great kid," said Paula Murray, the girl's great-grandmother. "I don't know how anyone could do something like that."
Her father, Richard Murphy, tried to speak at a vigil Sunday night but broke down crying, according to WEWS-TV. "She's the best thing that ever happened to me ... this is the hardest thing I've ever been through in my life," Murphy said.
"She saved my life," Murphy said. "I wish I could trade her places."
Associated Press writers John Seewer in Toledo and Amanda Lee Myers in Cincinnati and researcher Rhonda Shafner contributed to this report.
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