"Our focus has changed from the search for Jessica to a mission of justice for Jessica," Westminster Police Chief Lee Birk said. "We realize there is a predator at large in our community."
Birk says his department will do everything in its power to find the suspect.
The FBI's Behavioral Analysis Unit released a list of changes that a person committing a crime against a child would exhibit. Among them: sudden differences in appearance, missed appointments, being absent from work, or leaving town with no explanation. Police have ruled out Jessica's parents.
COMPLETE COVERAGE OF JESSICA RIDGEWAY'S MISSING CASE
The body was found not intact Wednesday by trash crews in the Pattridge Park Open Space area in Arvada. Authorities have spent the last two days working to identify the body and searching in and around the area for more evidence.
Westminster Police spokesperson Trevor Materasso says they are still encouraging witnesses to come forward and call their tip line at 303-658-4336.
Jessica's mother last saw her daughter walking to school on Oct. 5. The girl never arrived, setting off a frantic search by hundreds of law enforcement officials and prompting a nationwide Amber Alert.
Jim Yacone, FBI special agent in charge of the Denver division, said investigators would continue neighborhood searches. The U.S. Marshals Service, immigration officials and state Department of Corrections have been reviewing registered sex offenders in the area, he said, without elaborating.
Investigators have received more than 1,500 tips from the public, roughly 800 of which have been covered, Yacone said. Authorities also have searched more than 500 homes and more than 1,000 vehicles but still need the public's help.
"We want you to look for changes of habits, patterns, peculiar absences of those around you and report it to law enforcement," he said.
Signs of the tragedy have been everywhere in Jessica's neighborhood of modest, two-story homes with single-car garages.
Memorials were set up at Kensington Park and Chelsea Park, the place Jessica never made it to on Friday morning.
Dozens of people brought flowers, left balloons and lit candles in memory of Jessica. Purple ribbons and signs are all throughout Westminster.
During the past week, officers have searched homes and yards. They kept guard at crosswalks and photographed cars entering the neighborhood. Mailboxes and trees were encircled by ribbons in Jessica's favorite color, purple.
"I don't feel safe for my daughter anymore, anywhere," said Stacey Oppie, who lives in the neighborhood.
Two months ago, Oppie started letting her daughter play unsupervised with a friend at the park that Jessica customarily passed on her way to school. She doesn't intend to do that anymore.
"We're all a little bit on alert, but it's not fear. We're angry because this is a good neighborhood," Oppie said.
Jessica's disappearance hit close to home for Chelsea Bozsak, a senior at nearby Standley Lake High School, where Jessica's cousin attends classes. Students there wore purple Friday in support of Jessica's family.
"It's so scary because you never think something like this could happen in your community," Bozsak said.
Courtney Sullivan, also a senior at Standley Lake, said her father spoke to her and her younger brother about Jessica's disappearance.
"He's definitely talked to us about being more careful about our surroundings. You could see why," said Sullivan, a cross-country runner who often uses neighborhood streets. "I'm running in places where there's lights, busy roads, where I can get to someplace if I need to."
Retired FBI behavioral analyst Clinton Van Zandt told The Associated Press that tip-offs about the suspect could include someone suddenly growing a beard, getting a new haircut or other changes in appearance. Other clues might be out-of-character behavior, Van Zandt said.
Police have said they don't suspect Jessica's parents, Sarah Ridgeway, who lives with Jessica in Westminster, and Jeremiah Bryant, of Missouri.
The only substantive clue police have disclosed was the discovery of her backpack and water bottle in Superior, about six miles northwest of her home, two days after she disappeared. Police won't discuss what was found in the bag or test results involving it.
Law-enforcement leaders said they would not disclose further information publicly, saying it would either jeopardize or distract from the investigation.
"The commitment of the task force of investigators in this case will not waver, and our commitment and resolve to seek justice on behalf of Jessica will only grow stronger," Yacone said.
Jeffco Schools released the following statement Friday:
The heart of the Jeffco community is broken with the news of 10-year-old Jessica Ridgeway's death. We grieve for her family and friends; her Witt Elementary School community is devastated.
Upon receiving the news, Governor Hickenlooper released the following statement on Jessica Ridgeway:
"This is an unthinkable end to an unthinkable crime in our community. It is with a profound sense of sorrow that we learned of Jessica Ridgeway's death. On behalf of all of Colorado, we offer our deepest sympathies to her family and friends. The Colorado Department of Public Safety and other federal, state and local agencies involved in the case will continue to provide all of the support they can as the investigation continues."
COMMUNITY COUNSELING AND UPDATES
Starting Thursday night, Jefferson County is providing free counseling for dealing with Jessica Ridgeway's disappearance for those in the area who need it.
A crisis center was established at the Wells Fargo Arvada Building located at 7878 N Wadsworth Blvd. It is open Thursday from 5 to 8 p.m.
On Friday, it will be open from 8:30 a.m. to 8 p.m.
Highway 93 to Boulder has reopened, but 82nd Avenue between Highway 93 and Indiana Street remains closed as the investigation continues.
INFO ON HOW TO TALK TO KIDS ABOUT THE CASE
(KUSA-TV © 2012 Multimedia Holdings Corporation with The Associated Press)