More than 800 volunteers joined Westminster police officers, firefighters and the FBI in a massive search for a 10-year-old girl who disappeared Friday morning during the first three blocks of her walk to school.

Late Saturday night, police said they will bring a new team of search dogs in to help look for the child.

A helicopter was used in the search. Bloodhounds were used through most of Friday night. Although the dogs picked up a scent, it could have been older than Friday morning, Westminster police spokeswoman Cheri Spottke said.

“There were no strong hits,” she said.

A dive team went out on Ketner Lake in late Saturday afternoon to search with sonar for a body in the water, Westminster police spokesman Trevor Materasso said. They found nothing and left the lake around 5 p.m.

Police say they are following up on more than 100 tips about where Jessica may be.

Police are also scanning social media for information about the girl’s possible whereabouts.

Late Saturday evening, the Westminster Police Department sent out a note saying no additional volunteers are needed to help search for the child Sunday.

More than 800 citizen volunteers showed up in the bitter cold and freezing drizzle to search for Jessica on Saturday. Twenty-six times, teams of 50 people were sent out to search areas on foot. The search area covered was from 92nd Avenue to 112th Avenue, Indiana Street to Wadsworth Boulevard.

“This is an absolutely unbelievable outpouring of support,” Westminster Police Chief Lee Birk told a room of 150 volunteers waiting to load buses while more than 350 others stomped through nearby fields. “We accomplished more today than we thought we ever could. We certainly did not anticipate this kind of outpouring of support.”

Still, police urged concerned citizens to keep up with the case by following twitter.com/WestminsterPD and watching the Westminster PD Facebook page at facebook.com/pages/Westminster-PD/141296864304 for additional requests for help finding the girl.

Jessica Ridgeway’s mother stood in front of their home at 10768 Moore St. Friday morning and watched until her daughter was out of sight on her way to Witt Elementary School, 10255 W. 104th Drive, Spottke said. That was around 8:30 a.m.

Jessica routinely meets classmates at Chelsea Park, three blocks away, and then the classmates together walk the rest of the way to school together.

But on Friday morning the friends never saw Jessica, Spottke said. Jessica didn’t make it to school, Materasso said.

An Amber Alert, which is a national emergency notification, went out late Friday night after Westminster police were contacted. Also, 12,775 homes received calls from the police department notifying residents of the Amber Alert.

“It’s very concerning,” Spottke said. “She is still a young child. Mom is very distraught.”

Police investigators and volunteers collected socks and other items near Chelsea Park Saturday, Materasso said. The socks were placed in evidence bags.

“We can’t say at this point whether these are or are not related,” he said. Detectives will show the articles of clothing to Jessica’s mother and see if they belong to the girl, he added.

Jessica is 4 feet 10 inches tall, weighs 80 pounds and has blond shoulder-length hair. She has blue eyes and was wearing a black jacket and pink-and-purple glasses.

Spottke said police and firefighters went door-to-door Friday along the route from Jessica’s house to the school, asking residents for permission to search inside their homes and in their yards.

All but a few people complied, she said. Some people said they have small children and asked authorities to return the next morning when the kids were awake to search, she said. In other cases, no one was home.

“We searched all night,” Spottke said at 7:15 a.m. “We’ve switched up teams and we’re going out again right now.”

Authorities have greatly expanded the search area after many more volunteers arrived than were expected. The second shift of searchers will return to the homes where no one answered previously.

Police are reviewing past incidents for a possible connection, including the attempted abduction on Memorial Day of a 22-year-old female jogger at Ketner Lake in Westminster. A man tried to put a chemical-soaked rag over her mouth. The woman was able to fight her way free and called 911.

“It’s definitely something that we’re looking at,” Spottke said.

The woman’s assailant was described as white, about 5 feet, 8 inches tall with brown hair and an average build. He was wearing a blue cap, a black T-shirt, jeans and small rimmed sunglasses.

Another jogger was chased by a man with a similar description in July 2010, police said, warning those who use the area.

Authorities have checked up on every registered sex offender in the area to confirm their location. Flyers are being posted at businesses up and down Wadsworth Boulevard and left at residences.

Jessica’s mother, who works a night shift, had slept through the call advising that the girl had not arrived at Witt Elementary and so the search did not begin until around 4:30 p.m. Friday

Officials contacted the child’s father, who lives in Missouri. Materasso said the family in Missouri attended a child custody hearing there concerning Jessica Friday. He said he does not know the outcome of the hearing, but detectives do not believe it’s related to Jessica’s disappearance.

“At this time we don’t have any indication he is involved in any way,” Spottke said.

Jessica is a good child and a good student, Spottke said. Officials contacted every child in her class and all friends to see if she may have gone to one of their homes, but there was no sign of her.

The other adults in Jessica’s home include her grandmother and aunt.

Kirk Mitchell: 303-954-1206, Facebook.com/kmitchelldp or http://blogs.denverpost.com/coldcases