Updated

Authorities searching for a 10-year-old Colorado girl say they believe she was abducted by an unknown suspect, and they're confident her parents weren't involved.

Westminster police spokesman Trevor Materasso said at a news conference that police believe the girl was abducted by an unknown suspect. He said the focus of the case is not on her parents, who are cooperating.

"We're confident they are not involved in Jessica's disappearance," Materasso said.

Authorities investigating the disappearance are looking into whether it could be linked to the abduction of a girl in Wyoming.

Police in the Denver suburb of Westminster say they're aware of the case in Cody, Wyo., and were working with investigators there on Wednesday.

More On This...

A man lured an 11-year-old Cody girl into a sport utility vehicle on Monday saying he needed help finding his dog. She was released about four hours later and found by hunters.

Jessica Ridgeway of Westminster has been missing since Friday, when she left home to meet friends at a park for the walk to school. The fifth-grader never turned up at school.

Two days later, her backpack was found on a sidewalk in a neighborhood about six miles away.

Police say a fairly large group will be conducting an open-area search in the surrounding areas around Westminster, Colo., including the Eldorado Canyon. A second group will continue searching and canvassing the neighborhood around Ridgeway's home.

Nearly 125 people and 12 agencies are participating in the search, police say. Search dogs also will be used. The hashtag #JessicaRidgeway is currently trending on Twitter.

Meanwhile, police say they are pursuing tips from Nevada, Texas, Maryland and Maine, where a possible sighting of Jessica was reported.

In Maine, police say they’ve received reports of witnesses in the town of Dexter who saw a girl in a light blue station wagon with Colorado plates, KDVR.com reported. The license plate number is unknown. But Denver authorities say tips have come in from all over the country.

Click for updates from KDVR.com

The Associated Press contributed to this report.