AURORA, Colo. -- The search for a missing 6-year-old girl turned to a homicide investigation Thursday evening when police revealed that they believe Aarone Thompson was killed more than a year ago in her home by someone close to her.

"We believe that Aarone was murdered in the home," said Acting Police Chief Terry Jones.

Jones said the girl may have been dead for a year and a half, according to information they received from a close family friend who lives in Colorado.

He said the girl's father, Aaron Thompson, and his live-in girlfriend, Sheley Lowe, are "persons of interest."

"The children that were in the home, based on the information that we have, may be in danger so they have been taken into protective custody," Jones said. "We believe the children are in danger as a result of Aarone's death."

The seven other children who lived in the home ranged in age from 6 years old to 15 years old.

The home at Kentucky and Kepner has been sealed off, and police are in the process of getting a warrant to search the home as a crime scene.

Jones said that the father's report that the little girl ran away was a "fabrication" and he doesn't know what prompted the father to call police with a missing children's report on Monday. However, he said that Aarone's birthday was Nov. 30 and "something triggered, and this information was brought forward as a missing child when, in actuality, it doesn't appear to be anything of the sort."

Police say they have not questioned Aarone's father or his girlfriend since they made the announcement that the couple are in the center of a homicide investigation.

Investigators have conducted some preliminary interviews with Aarone's brothers and sisters but plan to interview them more thoroughly.

Nobody has been taken into custody.

The girl's body has not been found.

"I think the Aurora Police Department has put a great deal of effort into this case, right from the moment that we found out that we have a lost child. We took the father's appeal at face value. We did everything in our power with the assistance of the FBI, with Arapahoe County, Jefferson County, other agencies ... We put no less than probably 150 hours over a number of days into this, looking for this little girl. This is a very disappointing end to this investigation," said Jones.

Jones said the case started to take this drastic turn when investigators received a call late Wednesday night from someone close to the family.

"It shed some light on the fact that Aarone Thompson may have been murdered in this house on Kepner Drive, not recently, some time ago, but up to a year-and-a half ago," Jones said. "The individual did have the information (for some time) and I don't know what prompted the fact that the information came forward other than the media coverage that Aarone Thompson was missing."

"Over a period of days, of course you always have concerns, some of those things had to do with the family -- the demeanor, the inability to get things accomplished that we'd thought a family would want to get accomplished upon reporting a missing child. We were very very fortunate that someone's conscience prompted them to call us with a piece of information that enabled us to get a search warrant for the home," said Jones.

The girl's biological mother, who lives in Detroit, told 7NEWS that she hasn't seen Aarone since October 2001. The girl's grandfather and grandmother said they talked to Aarone last Christmas, a family spokesman said.

Jones said that the homicide investigation could take some time.

Police have been to the Thompson home before. Aarone's brother, 11-year-old Aaron, was reported missing from the home one month ago. He came back a day later.

Search Halted Early On

The case of a girl who allegedly fled her house after fighting over a cookie started to change course earlier in the afternoon when police said that they would no longer search for her after looking for her for more than three days.

"We feel that we have covered the areas that a child of her age could have walked to," said Aurora police spokesman Marcus Dudley at an afternoon news conference.

A police spokesman for the father's family, Sam Riddle, told 7NEWS that the portrayal of the family as uncooperative is false. He said every member of the family has given DNA samples, fingerprints and answered all of the questions posed by investigators.

"You can't cooperate more than this family," said Riddle. "Colorado law enforcement authorities ought to be showing a lot more compassion for this family and not misportraying them as being noncooperative ... Aurora police -- they need to go back to training because this is family that is in deep pain. Right now the grandfather and other members of the family are passing out leaflets throughout Aurora, trying to find this little girl."

He said the family is looking to hire an attorney.

"The thing that disturbs me a lot too is the disparity in treatment that is being afforded to the Thompson family, vis-a-vis, for example the (treatment) that was accorded to the JonBenet Ramsey family in Boulder, Colo. There is a great disparity in terms of how this family is being treated versus the family of JonBenet Ramsey a few years ago," Riddle said.

Police acknowledged Thursday that the family did cooperate by allowing detectives to conduct one-on-one interviews but police said Aarone's father was still not completely cooperating.

"The cooperation has improved but there's still more cooperation that needs to take place," Dudley said.

Aurora police asked consultants with the National Center for Missing and Exploited Children to step in and help with communication.

"If they can work with the family a little bit to see if maybe we could get the father to assist us by maybe pointing out areas he searched prior to making the call to the department," said Dudley.

Police just wanted Aaron Thompson to take them to the exact locations he searched before making Monday's call, but Aarone's father never granted that request.

Aarone's biological mother, who lives in a woman's shelter in Detroit, also urged her estranged husband to fully cooperate with all law enforcement requests.

"I feel like something happened in that house. I feel like something is being covered up -- people are not cooperating," said Aarone's mother, Lynette Thompson. "My gut, deep down inside me tells me something happened to my daughter. From Monday to today, there's been no answers."

Lynette Thompson had said that when she first learned of her daughter's "disappearance" she told Aurora police to go dig up the back yard. She had said that her husband is known to have a temper and doesn't entirely believe his story that Aarone just fled the house after a fight.

On Wednesday, the FBI searched the girl's home and a trash truck. Agents found some items of interest and took them away for further inspection, but police would not say what the items were or whether they are involved in the case.

Why Wasn't An Amber Alert Issued?

Aarone's family had expressed anger that an Amber Alert was not issued on Monday afternoon when she first disappeared.

"Law enforcement authorities were in that house within two hours after Aarone was reported missing. Yet an Amber Alert was never issued. I don't care what bureaucratic reasons they may give, the bottom line is, when a 6-year-old girl goes missing, every apparatus at the disposal of law enforcement in our community should be put out there," Riddle said. "An Amber Alert should have been done as just a matter of course."

However, the Colorado Bureau of Investigation is standing by its decision not to issue the alert. The CBI said it never had enough specific information about a suspect or a vehicle to meet the criteria for issuing an Amber Alert, and without that information they say an alert does no good for the victim or the public.

In the three years since Colorado began the program, 36 Amber Alerts have been issued. The criteria requires the victims to be under 17 and police must be convinced that there is immediate danger of harm or death. Thankfully, all of the children involved in an Amber Alert were returned home safely. But the CBI said in Aarone's case, the Amber Alert would not have helped because the early details were just too sketchy.

The CBI said the standards are important. Otherwise, they fear the public will tune out the alerts altogether.

"We want them paying close attention when we do decide to issue those," a CBI spokesman said.

Police also admitted that their search was delayed by about 90 minutes because of a miscommunication with the girl's father.

Aaron Thompson reported that his daughter was a runaway, and it was only after he came down to police headquarters to fill out a report that they realized they were dealing with a very young girl and not a typical teenage runaway.

Volunteers Were Willing To Help

The experts from the National Center for Missing and Exploited Children flew into Colorado Wednesday and were willing to help organize volunteers for a massive search. Unfortunately, that was never needed.

Dozens of neighbors had come by the girl's house, trying to offer support. A young mother dropped off a stuffed animal and a candle near the home Thursday morning.

"It's not about me. It's not about anybody else. It's just showing support. It's about this little girl and showing her that we care about her and support her," said Tracy Tobin. "We wish her the best and want her to come home."

A man also placed a sign on the fence post near the house that said, "Aarone, we miss you. We love you. Please come home Aarone."

Experts say that 99 percent of children who disappear do come home and it's often a misunderstanding. But it's never to late to learn how to keep your kids safe. People with the Polly Klaas Organization say the most important thing you should have is an updated picture of your child. You should also write down your child's eye and hair color and any distinctive features.

It may sound simple, but those things can sometimes be hard to remember when you're in a crisis. And if your child disappears, don't wait. Call 911 immediately.

Aurora police have set up a tip line. If you have any information about the case, call (303) 739-6050.

Resources:

To order a free Child Safety Kit click here
National Center For Missing and Exploited Children