Authorities have arrested a man they are calling a person of interest in the kidnapping and killing of a northeast Florida girl whose body was found in a landfill after she vanished on her way home from school.

Clay County Sheriff Rick Beseler said a man who had lived in the girl's neighborhood was arrested in Mississippi Thursday on 29 charges of possession of child pornography. The man, Jarred Harrell, 24, has not been charged in the death of 7-year-old Somer Thompson.

SLIDESHOW: Somer Thompson Murder

Harrell, who was arrested in Meridian, Miss., had lived until recently in a home near Somer Thompson's. Authorities were searched that house Thursday. Deputies and an FBI forensics team were seen searching its front yard with rakes and shovels

Beseler, who announced the arrest during an evening news conference, said a vehicle had also been searched.

The 7-year-old girl vanished Oct. 19 as she was walking home from school, sparking a search that lasted for two days. Investigators sorted through more than 225 tons of garbage at a landfill some 50 miles away, across the state line in Georgia, before their worst fears were realized: Sticking out of the rubbish were a child's lifeless legs.

Authorities have checked into thousands of tips in the case in the nearly four months since, but no one has been charged in the killing. The girl's mother, Diena Thompson, said she didn't want to get her hopes up that a break had been made in the case.

"I'm not speculating on anything. I don't want to get my hopes up and I don't want to get my hopes down," she told The Florida Times-Union. "I'm going to put my faith in God."

P.J. Simms, who has lived in the neighborhood 17 years, said she hopes authorities find what they are looking for.

"I just hope they find what they were looking for because it has been a long time coming. This is the first time anything like this has ever happened. It's broken our hearts," she said. "You used to see 40 to 50 kids out here every day, now there's always somebody with them."

Simms said she knew Somer because she used to babysit for the girl's friend.

"She was a sweetheart, just very loving. She always wanted to be a part of everything. I hope and pray to God that this is it so we can finally let the kids play."

Click here to read more on this story from MyFoxOrlando.com.