ORANGE PARK, Fla. -

Wearing her daughter's favorite color -- purple -- and surrounded by her closest family and friends, Diena Thompson, the mother of 7-year-old Somer Thompson, who was killed in October, thanked all of those who have supported her and those who were involved in the investigation leading to the arrest of Jarred Harrell, who is now charged with Somer's murder.

"One hundred-fifty-eight days ago, my 7-year-old twin daughter was walking home from school like a child should be allowed to do," Diena Thompson said. "And on this day, someone took her away from me, her siblings, my family and the world. A monster -- that's all this person is is a monster."

"Somer was such a bright star that never got her chance to shine," she said.

Harrell, 24, arrested in Mississippi on child pornography charges unrelated to the Somer case last month and extradited to Clay County, was charged at 6 a.m. Friday with premeditated murder and sexual battery.

"Justice is not fast as an impulse, and that's what this monster did: He had an impulse, and he took something away from me that no one will ever be able to give back to me," Thompson said.

Clay County deputies said that when Somer disappeared, Harrell lived in a house on Gano Avenue that she walked by every day on her way home from Grove Park Elementary School. His house was only a few doors from where Somer was last seen alive. Her body was found two days later in the Charlton County, Ga., landfill where Orange Park's trash is dumped.

"I stood here in front of all of you (158) days ago and said that 'We're coming to get you. We will get you. So I would like to take this opportunity to say to Jarred Harrell, 'We got you, and you ain't getting away,'" Thompson said.

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Thompson said she had never seen Harrell in the community before, labeling him a complete stranger.

"I had a feeling it was someone nearby, I just didn't know he was that close," Thompson said. "Im glad he's in jail, but there's many more lurking in the depths. We've got to keep them away from our children. Something has got to give."

Thompson's older sister, who was standing next to her at the emotional news conference, appeared to be faint and fell forward, though she was said to be OK.

The emotion and heartache that's surrounded Somer's family and the community for the last five months could be seen on Thompson's face as she fought back tears.

"Somer is forever going to be in my heart and my mind," Thompson said.

Samuel Thompson, Somer's father, released the following statement via the law office of Leigh, James & Associates on Friday regarding Harrell's murder charge:

"Samuel Thompson would like to thank the Clay County Sheriff's Department for their diligent efforts in this matter. At this time, Mr. Thompson is not prepared to make a public statement. It is his intention to let the legal process run its course. On behalf of himself and his family, he would like to thank everyone in advance for respecting their privacy."