Alisa Maier, whose disappearance prompted an Amber Alert, was found in Fenton, Missouri, about 10:15 p.m. Tuesday (11:15 p.m. ET) at a car wash and taken to a hospital, the St. Louis County police department said.
Witnesses said they first saw and heard a dark-colored car, maybe black or brown, with an extremely loud muffler at the car wash. Then they saw the a child walking in the area that they first mistook as a boy, said St. Louis County Police Chief Tim Fitch.
"We have reason to believe she was associated with the car at the car wash," said Fitch.
The witnesses called police who came to area and realized that the child was Maier, Fitch said.
Anita McKlevis, who lives across the street from the family, said Alisa's mother was "just beside herself" and tried to pursue the man who abducted the girl.
"She jumped up and went across the street, got into her van and took off," McKlevis told HLN's "Issues with Jane Velez-Mitchell."
She said the children were regularly supervised by parents or grandparents while playing outside: "I never seen this little girl without her parents," McKlevis added.
Michael Kaste, an agent from the FBI's St. Louis office, said between 75 and 100 law enforcement officers -- including about 30 FBI agents -- and about 50 volunteers took part in the search. Investigators also questioned known sex offenders about the girl's abduction, he said.
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