"(An arrest) will depend upon when the investigators and prosecutors look at that and say they've got an overwhelming case to put somebody in jail and keep them there," said Pete Kampfer, Colorado City police spokesman.
There are other persons of interest in addition to Adkins, Kampfer said, and investigators are working to piece all the evidence and information together.
"All the agencies are engaged, and nobody's lost any traction."
The investigation is continuing in both directions – criminal, in the event Hailey was kidnapped or harmed, and missing person, in the event she left on her own.
"Our prayers are that Hailey will be returned in good order," he said. "You try to keep the faith."
Hailey was last seen by Adkins on Dec. 27. He told investigators she was going to stop by her dad's house, then to spend the night with a friend. She never made it nor was she expected at either location.