Mystery of Who Killed Florida Girl Baffles Detectives, as Hunt Turns Up No New Leads

Detectives searching for a 7-year-old's killer have interviewed more than 100 sex offenders living nearby, sifted through tons of garbage and combed the well-kept neighborhood where Somer Thompson disappeared.

Missing child posters featuring the slain girl's face, framed by her thick brown bangs, still plaster nearly every utility pole along the mile-long route from her elementary school to her suburban Jacksonville home.

Somer was last seen alive walking along the sidewalk in front of a vacant house, and authorities said Friday that they're searching for anyone who saw what happened to the 7-year-old after that. Investigators sifted through evidence from that vacant house and the Georgia landfill where her body was found Wednesday.

So far, no witnesses have come forward to say they saw Somer attacked or abducted, sheriff's spokeswoman Mary Justino said.

"What we've been trying to figure out is who frequents that area, because obviously it's more than just the people who live there," she said.

LIVESHOTS: Police ID Body as Missing Florida Girl

SLIDESHOW: Somer Thompson Disappears on Walk Home From School

The child's teary but resolute mother appeared on television interviews and warned her daughter's killer: "We'll get you." She pleaded for anyone with information to "please, please tell" police.

The day after the child's body was identified, authorities said they had ruled out all 161 registered sex offenders who lived within a 5-mile radius of Somer's home. Despite doggedly pursuing hundreds of leads, police have not made an arrest.

Somer vanished while walking home from her elementary school on Monday afternoon. The vacant house is on her route through a heavily populated, well-manicured neighborhood, and witnesses last saw the girl alive in front of it. She had gotten upset as she walked home with other children Monday and ran ahead of the group. Somer never made it home.

Neighbors said they were used to watching out for each other's children as they walked to and from school.

"Everybody knows everybody here. If there was a stranger on the street, we'd be looking at watching where they were going, seeing what they were doing here," said Monica Loeb, a family friend of the Thompsons.

Somer's mother, Diena Thompson, had a friend greet her children as they came home from school Monday because she was working, according to a police report. When Somer didn't arrive with the other children around 4 p.m., the friend sent Diena Thompson a text message. She raced home, and flagged down a passing police officer while she, her other children and her boyfriend scoured the neighborhood.

An autopsy has been completed and investigators know how Somer died, but authorities won't disclose their findings or any details about the body.

At a vigil held outside the Thompsons' home Friday night, the mother said she would not be able to see her daughter's body.

"They are going to give me a lock of her hair," Thompson said.

Mourning neighbors and others have gathered every night outside the home. On Friday, the mother joined them to sing Somer's favorite song, "You Are My Sunshine."

Diena Thompson declined to be interviewed Friday by The Associated Press. She spent part of the day making funeral arrangements, and a law enforcement officer was seen carrying a child's white dress from the family's home. A viewing will be held Monday night and a funeral will follow on Tuesday.

But Thompson appeared red-eyed on all three network television shows and said on ABC's "Good Morning America" that investigators will catch her daughter's killer.

"We're coming for you," she said. "We'll get you, and hopefully justice will be served."

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