Investigators searching a creek in a rural part of Caldwell County came across some evidence Wednesday, sources told WCNC-TV in Charlotte, N.C.
Locals say possible human remains were recovered but authorities are not describing what they found.
Emily Dietrich, Zahra's mother, who has not had contact with Zahra since she was a baby, was on her way to Hickory, N.C., WCNC reported.
She told Australia's Channel 7 News she had been trying to find Zahra when she learned the 10-year-old had disappeared.
"I felt robbed before she was taken. Now I just feel broken," Dietrich told the Australian television station.
In Caldwell County Wednesday, crews were searching along a creek, both in the water and along the ground.
"An area that's high priority to us right now, we are doing 3-foot spacing so our guys are basically shoulder to shoulder going through there," said Tommy Courtner, emergency management coordinator in Caldwell County. "We're moving the brush out. We look at every piece of that ground."
Around noon Wednesday, investigators ordered the media from the area and closed a local road and the airspace overhead without explanation, WCNC reported.