Sheriff's deputies have deployed trained cadaver dogs in the search for a 2-year-old girl in Orlando, Fla., who has been missing for more than a month.

A sheriff's investigator, Sergeant John Allen, said Friday that authorities don't rule out the possibility that Caylee Marie Anthony is still alive.

Deputies say the girl's 22-year-old mother, Casey Marie Anthony, was arrested Wednesday on charges of child neglect and criminal obstruction. They say the woman told investigators she had dropped off her daughter at a baby sitter last month but hadn't seen her since. The woman didn't contact police until this week, officials say, once relatives became concerned.

The woman's lawyer did not immediately return messages seeking comment.