The mother of a 7-year-old Florida girl found murdered in a landfill praised the hard work of authorities combing through evidence to find clues to her daughter's killer.

"These detectives — excuse my language — are busting their (expletive) to find it. Because it's an it," Diena Thompson said Saturday, referring to the killer of her daughter, Somer.

Thompson spoke to dozens of mourners and supporters holding a vigil outside her home. They gathered around a huge makeshift memorial of Hannah Montana balloons, stuffed animals and candles that have burned so long that the wax has melted into the grass.

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"I just want you guys to know I really do love you," Thompson said. "I can't believe the support I've been given."

Dozens of parents, their young children in tow, have filed past the memorial. Many were angry, sad and afraid as they waited for developments in the search for what happened to Somer as she walked home from school Monday.

The girl was last seen alive walking along the sidewalk in front of a vacant house, and authorities said they're searching for anyone who saw what happened to her after that. Investigators have finished sifting 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, Clay County 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.

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.

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

Marie Spires of New Richmond, Ohio, is Somer's maternal great grandmother. She walked out of the family's home Saturday afternoon to look at the growing memorial.

"I'm shocked that this could happen in this type of community," she said. "And that no one would see or hear anything."

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

Spires said she doesn't know how the little girl died and detectives have not shared any theories about who killed Somer.

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

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

The mother spent part of Saturday meeting with officials of the First Baptist Church, planning her daughter's viewing on Monday and funeral on Tuesday. After the funeral, mourners plan to release hundreds of purple balloons. Purple was Somer's favorite color.

The viewing and funeral are open to the public, but graveside services and the burial are private. The slaying has shocked the Jacksonville area, and inspired many people from outside the area to drive to Orange Park to show their support.

Vonda Durden, 60, visited the site from Woodbine, Ga., with her 14-year-old granddaughter.

"It's a nice-looking neighborhood, nice houses, nice people," she said, shaking her head. "And you can't even let a little child walk these streets."