Investigators are ramping up search efforts to find missing 3-year-old Mariah Woods by asking for the public's help.

The FBI is planning to conduct an on-foot search at 8 a.m. Friday morning in Onslow County. The massive search effort is happening just one day after investigators announced that they may have found evidence in the 3-year-old's disappearance.

Authorities are asking volunteers to meet them in Jacksonville, North Carolina to help cover areas as the search intensifies and expands.

Volunteers need to arrive at the Dawson Community Church located at 2311 Dawson Cabin Road between 8 a.m. and 9 a.m. Be prepared to show ID to register, authorities said. They also asked volunteers to wear appropriate attire and bring your own water or snacks. No horses or four-wheelers, the search will consist only on foot.

Volunteers will be broken up into groups with a team leader and will walk in a straight line no more than 10 feet apart, authorities said. Each search could last anywhere from four to six hours.

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"Search your own properties, buildings, abandoned cars, anything that would help us to ensure we have searched every place possible," an FBI spokesman said.

After searching local bodies of water and abandoned land in Onslow County, the FBI said Thursday that they gathered evidence that may be connected to Mariah's disappearance.

The items are now headed to Virginia for testing.

"Those items will be a priority for testing so we can determine whether or not they contain any evidentiary value," an FBI spokesperson said.

As of Thursday, investigators said they have already followed up on more than 140 leads and conducted over 100 interviews.

Earlier in the week, the FBI released images from a Walmart surveillance of an adult woman walking with a child believed to be Mariah. However, officials later determined the girl in the pictures were not the missing child.

"As a father and a grandfather, I'm looking at a little 3-year-old girl and I'm emotional about this," a representative from the Onslow County Sheriff's Office said. "We want to find Mariah and bring her back."