WESTMINSTER, Colo. - As the search for 10-year-old Jessica Ridgeway continued Tuesday, a day after FBI agents and detectives went door-to-door in the girl's Westminster neighborhood, asking people if they could search their vehicles, yards -- even their homes.

A reporter with The Denver Channel, Lance Hernandez, talked with residents who said they voluntarily let investigators search their property.

"My attitude is check. Go ahead, check. Do what you need to do," said neighbor Kathleen Rodriguez. "I know she's not here, but they need to know that."

The agents were exploring if the girl might have taken shelter in a parked car during the cold weekend, if she snuck into a house or garage or if someone might be hiding her, homeowners told Hernandez.

Residents said the agents were also asking, "Did you hear anything out of the ordinary-- any noises or slamming doors? Or have you seen anything out of the ordinary?" Hernandez recounted.

Neighbor Kerry Viney said the investigators also asked if he'd noticed suspicious vehicles or any workers who had recently come into the neighborhood.

Meanwhile, Jessica's mother, Sarah Ridgeway, came out of her home Monday evening, and made an emotional journey. As friends supported her arms, the mother walked down the street where Jessica was last seen on Friday morning as she left for school. She never arrived.

FBI agents spent more than an hour meeting with Jessica's family members at their home on Monday morning.

Steve Kesel, who was house-sitting for a friend in the neighborhood, let investigators search the home, including its attic.

"I'm just helping out," Kesel said. "They're just asking, 'Did you see any suspicious things going on in the neighborhood (like) different vehicles?'

Referring to Jessica's mother, Kesel said: "I hope for a speedy, speedy happiness for this lady -- putting the kid back in her mom's arms."

Investigators were sifting through more than 300 tips from the public.

Sources tell The Denver Channel that investigators are looking into a report that someone saw a suspicious van in the Ridgeway's neighborhood on Friday morning when Jessica disappeared.

That sighting came a day after two girls -- ages 10 and 11 -- told Arvada police that a man in a white van followed them as they walked home from Lawrence Elementary. That school is only about 8 miles from Jessica's home.

Arvada police are investigating the van incident, and Westminster police say they haven't ruled out a possible connection with Jessica's disappearance.

Twelve agencies are involved in two simultaneous searches.

Twelve different agencies are cooperating on two simultaneous searches for Jessica.

She was last seen walking to Chelsea Park in the area of 107th Avenue and Moore Street around 8:30 a.m. Friday, where she was to meet several friends before walking to Witt Elementary School. Jessica never showed up at the park or at school.

Officers with dogs searched the neighborhood near Jessica's home again Monday, including several fields, said Westminster police spokesman Trevor Matterasso

“Every search is crucial, that’s why we’re conducting those and that’s why we’re repeating. We’re still in Jessica’s neighborhood, obviously. That area has been searched. Areas are being searched a second and third time. We’re focusing on the area she was last seen in and again we’re focusing on the area where that backpack was found," Matterasso said.

Additionally, Matterasso said 125 searchers are looking in a triangular search area around the location where the girl's backpack and water bottle was found over the weekend. That triangular area is defined by Highway 128, Highway 36 and Highway 93, including El Dorado Canyon.

Jessica's backpack and water bottle have been taken to a Colorado Bureau of Investigation lab to be analyzed.

Matterasso urged parents to speak with their children about Jessica's backpack, which was discovered near the intersection of Andrew Drive and Alpha Court in Superior.

“We don’t know when the bag was put there. Obviously over the weekend, kids were out of school. There is a chance that the kids may have gone by, playing, riding bikes. We want parents to talk to their kids about it," he said.

Erica Manuel's son sits next to Jessica in class. She is being honest with her son about what happened.

"Kids can't be kids anymore these days. They have to be constantly watched by adults and by themselves," she said.

Anyone who might have any information about Jessica's disappearance of current whereabouts is asked to contact police at 303-658-4336 or pdamberalert@cityofwestminster.us. Matterasso said those tip lines have already received approximately 300 calls.

The CBI, which was closed for the federal holiday Monday, brought in resources to collect DNA samples from the Ridgeway home and the backpack.

No volunteers are being accepted for the search Monday, but Matterasso said several were engaged in spreading fliers with Jessica's picture. He said it was vital that everyone focus on her physical features and not on her clothes.

“In the amount of time since [she was reported missing], there’s a likelihood that she has changed clothes," he said. "We’re asking people to really focus on Jessica, her facial features. If you see a flyer, really look at Jessica and burn that image so you remember what she looks like.”

No person of interest in the investigation.

There is currently no person of interest in the investigation, Matterasso said.

About Jessica's father, who lives in Kansas City, Matterasso said that there was a custody dispute but no members of the girl's family are suspected in the disappearance.

"He's devastated, so is mom, they're both absolutely beside themselves," Jessica's grandmother, Donna Moss, said Saturday. "If you see something or know something, please, please, please just call. Even if it's the wrong information, just call."

Asked about reports of a suspicious van seen in Jessica's neighborhood Friday morning, Matterasso said there was no indication that a random child abductor is on the loose.

Still, police are taking precautions. Matterasso said officers were stationed Monday at every elementary school in Westminster and surrounding communities.