Greeley Police say her death does not appear to be accidental.
The girl went missing from her home on March 28 when she left her home to walk to a birthday party but never arrived.
"This is a homicide investigation, a murder investigation at this point," Greeley Police Chief Jerry Garner said during a Thursday afternoon news conference.
"It's devastating, but it's a relief to know that she's found," Cindy Rogers, a friend of the Wilson family, said after hearing the news. "She's going home. She's going to go home."
"It was horrifying. It's horrifying to the community. It's horrifying to the family, to everyone. I just hope we can find who did this," Cheryl Fenerith, another family friend, said.
A worker found her remains around 6 a.m. Wednesday in a drainage ditch near 29th Street and 35th Avenue.
Garner says the area where Kayleah was found was searched twice since she disappeared.
"I can't tell you for positive if anybody poked their head in that exact spot or not. I honestly don't know," he said. "There were dogs used in the search and they did not come up with anything useful to us."
Police say the Weld County Coroner's office used dental records to identify her body.
Garner says there are a wide range people who are considered of interest in the case.
"We have recovered items of evidence, but I can't really go into what we've recovered at this point. Sorry I can't give you more," Garner said.
Garner says the items were recovered from several locations.
Garner says they also have a cause of death, but did not release any details.
"The death didn't occur, let's say, within a day or two of when the body was found. In other words, it occurred some time ago," he said.
Garner met with Kayleah's mother, April Wilson, earlier on Thursday.
"What we were able to promise her is our pledge that we don't give up on cases like this. We don't give up on them," he said.
Garner says the family was not at the news conference because they did not want to speak to the media at this time.
"There is nothing to indicate that there's a family member that is a suspect in this case, but like I say, we're looking at a whole variety of people at this point and it would be wrong for me to say any specific person is not a suspect. We have nothing that turns us to the family though," he said.
Community reacts to news
Family, friends, and even complete strangers came to a makeshift memorial set up at the site where the body was found to pay their respects on Thursday afternoon. Too many mothers to count, and their children in hand, came after they heard the news the body found was Kayleah.
Several of the mothers say they hope their children will take away lessons from this: learning lessons in sympathy and learning the importance of staying aware.
Wilson family friend Michelle Thompson said, "Protect your children. Please protect your children."
Even though Thursday's news brought some answers, in some ways, it created questions that will never be answered.
"How could anybody could do this to a child. Why? Why?" Fenerith said.
"What did she do wrong to deserve this? She didn't deserve any of this," Rogers said.
Kayleah's body was found in a ditch that sits next to a church and a cemetery. It is this bit of irony that brings solace to those who lost Kayleah. Those paying their respects also focused on a symbol engrained into the tree planted right above where Kayleah was found: a symbol that some say mimics a heart, and others say looks like angel wings.
"Maybe that's an angel showing us that she's got her wings now and she's free," Fenerith said.
There is also a lot of concern surrounding April Wilson, Kayleah's mother. One of April's friends told 9NEWS she is doing as well as can be expected for someone who just received news that they lost a child. She said April took the news particularly hard because she is the one who has had the most hope from the beginning.
Investigation into death continues
Garner says the FBI and the Colorado Bureau of Investigation are assisting in the homicide investigation.
Sources tell 9Wants to Know the amount of decomposition to her body was so extreme that investigators could not immediately tell whether it was male or female and were also unable to determine her age.
Sources say the body was underwater for a substantial amount of time. Investigators say it is possible the body was laying elsewhere and Tuesday's rain storms could have dislodged it and carried it into the ditch.
"There's a number of possibilities, but we really don't know for certain the answer to that," Garner said.
Garner addressed speculation that Kayleah was seen on video in a parking lot of the Greeley Mall.
"There were people in the parking lot that were on video, that one of them might have been Kayleah, but we have not confirmed, the picture is not good enough to say, 'Yes, this is her.' So that's supposition. There's no positive ID that she was in that parking lot," Garner said.
A candlelight vigil for Kayleah was held on Wednesday night at the ditch by family and friends.
Greeley Police are still looking for additional tips related to the investigation. Anyone with information is urged to call 970-350-9600. There is a $20,000 reward for information that leads to an arrest and conviction.
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