Search and rescue teams are combing areas around where a 10-year-old Washington girl disappeared last month after police received numerous tips, local FOX affiliate Q13 reports.

Lindsay Baum vanished June 26 as she walked from her friend's house to her own home. Her mother called police when she didn't return that evening.

Undersheriff Rick Scott says so far in the investigation they've received about 700 tips.

"This is a girl with no means, no money, and no true opportunity to leave. We have nothing specifically that is pointing us in any direction that is going to allow us to rule out any scenario ... this may be a worst case scenario criminal investigation involving a predator or predatory behavior," Scott told Q13.

Several agencies, including the FBI, Crime Stoppers and the Pierce County Sheriff's Office, are assisting in the search.

In June, Baum's mother said she believed her daughter is alive but has been kidnapped and taken out of the area.

"I don’t think she’s in McCleary. I don’t," Baum told The Daily World of Aberdeen, Wash. "Why would they keep her in McCleary? Whoever took her went on the freeway. There are three ways to get out of McCleary and all three ways there are freeways within five or 10 minutes."

Baum said she hasn't given up hope.

"I’m begging whoever had her will take her to a gas station or a grocery store or a restaurant where she can go to a pay phone and call 911 and say ‘I’m Lindsey Baum’ so we can trace her and find her," Baum said. "Just let her go. Give her a chance. Let her come home."

Lindsey is 4 foot-9, 80 pounds, with brown hair and brown eyes, last seen wearing a light blue hooded pullover shirt and blue jeans.

Anyone with any information is asked to call the Grays Harbor Emergency 911 Center at (360) 533-8765.

Click here for more on this story from Q13FOX.com.

The Associated Press contributed to this report.