ATLANTA -- Authorities said Saturday they believe a hiker who disappeared from the northern Georgia woods on New Year's Day is dead, and they charged the man who was reportedly last seen with her with kidnapping.

Union County Superior Court Judge David Barrett signed a warrant charging Gary Michael Hilton with kidnapping with bodily injury in the disappearance of Meredith Emerson, said Georgia Bureau of Investigation spokesman John Bankhead.

Authorities were serving the warrant on Hilton on Saturday evening. The warrant was issued "based on evidence recovered in various locations," Bankhead said. He did not elaborate.

Bankhead said the search for the 24-year-old woman, who was hiking with her dog in the Chattahoochee National Forest, is now focused on finding her body.

"The search has changed from rescue to recovery, based on the evidence we've uncovered so far," Bankhead said.

Hilton is already in federal custody near Atlanta, held on a warrant for failure to appear in federal court for a charge of abandoning property in a national park.

The search continued into Saturday evening. Teams focused on a five-square-mile area of rugged mountain territory about 90 miles north of Atlanta in the Chattahoochee National Forest, near where Emerson's car was discovered Wednesday, Bankhead said.

The search had been focused on Vogel State Park, where Emerson was last seen on New Year's Day hiking with her black Labrador retriever, Ella.

Also on Saturday, authorities went to Forsyth County in the Atlanta suburbs, where Ella was found Friday at a grocery store, Bankhead said. Authorities identified Ella using her implanted microchip, Union County investigator Kimberly Verdone said.

Police picked up Hilton at a convenience store in the Atlanta area, Verdone said.

The Georgia Bureau of Investigation declined to specify how investigators learned Hilton's name and other details about him.

Karrenbauer described Emerson as an experienced hiker who has a blue belt in martial arts. Other friends said she was familiar with the trail near where her car was found, having jogged on it several times with a partner.

Emerson, formerly of Longmont, Colo., recently moved to Buford, Ga., a suburb of Atlanta.

Vogel is one of Georgia's oldest and most popular state parks. The area includes a segment of the Appalachian Trail, the famous hiking route that stretches from Georgia to Maine.

On the Net

• Meredith Emerson search: www.helpfindmeredith.com