ORANGE PARK, Fla. -- The body of a white child has been found a landfill in Georgia and the sheriff's office said many factors indicate the body is that of missing 7-year-old Somer Thompson.

"It's with deep regret and sadness that I have to inform you that a body has been found in the landfill in Folkston, Georgia. The body appears to be that of a small child," Clay County Sheriff Rick Beseler said.

Beseler said the garbage in the dump was collected in the Orange Park area, which is where Somer was last seen. Folkston is around 55 miles from Orange Park.

"As a matter of routine course, as soon as we find a missing person case has been initiated, we begin following the garbage trucks. We had the garbage secured overnight, and the body was discovered today," Beseler said.

Beseler said an FBI forensics team is on its way to the scene to investigate.

A $30,000 reward is being offered in the case.

Gov. Charlie Crist also spoke at the news conference Wednesday afternoon where the announcement was made. He said the body is likely Somer's.

"It's not absolutely concluded that what's been found in the dump Georgia is Somer, but it looks like it probably is," Crist said.

An autopsy will be performed on the body by a Georgia medical examiner.

Somer's mother went on all three national network morning news shows with a tearful appeal for the child's return.

"Somer, you're not in trouble. If you're scared, just come home," Diena Thompson said on Wednesday. "And if somebody has her, please, please bring her back to us. She belongs with her family."

"She's got a twin and he's lost without her," Thompson said in a later news conference.

Clay County Sheriff Rick Beseler said investigators are baffled.

"Somer disappeared off the face of the Earth. We just don't have a clue right now where she is," Beseler said.

He said officers have expanded the initial search area and interviewed about 75 known sex offenders in a five-square-mile radius. Teams of volunteers are walking arm-to-arm through the woods, and deputies are using helicopters and search dogs.

"We just really need a break in this case. We need a tip, we need a phone call," Beseler said. "Somebody knows where Somer is, and we need that person to call us."

Investigators have said they suspect foul play.

"The likelihood she has been taken by someone is high," the sheriff said.

The girl vanished on her mile-long walk home from school Monday in Orange Park, near Jacksonville.

Thompson said Somer was squabbling with another child, and her sister told her to stop. The girl got upset, walked ahead of the group and wasn't seen again.

Orange Park is a suburb of Jacksonville just south of Jacksonville Naval Air Station. The area where the girl disappeared is a heavily populated residential area with homes, apartment complexes and condominiums. There are wooded areas and retention ponds.

Orange Park is also about 50 miles north of Satsuma, where Haleigh Cummings disappeared in February. She has not been found.

Authorities said they are searching two landfills in Florida and Georgia as precautionary measures, not based on tips.

Gov. Charlie Crist was to join Beseler for a news conference later Wednesday to give an update on the investigation. Watch Local 6 News for more on this story.