The woman who brought little Jessica Cortez to a free clinic in Los Angeles was arrested after clinic staff recognized Jessica and called police. Patricia Cornejo, 34, was booked on kidnapping charges.
Cornejo took Jessica to the clinic because the girl complained of a sore throat, police said.
"The motive remains a bit hazy right now," Police Chief Martin Pomeroy said Wednesday. "We're not sure why this woman did what she did."
Pomeroy said Wednesday that Cornejo, a mother of four children, has had no major run-ins with police and has no record with child services authorities.
Jessica apparently spent the entire time of her disappearance in the woman's home and was not physically harmed in any way, Pomeroy said.
"I don't believe there was great force used and perhaps nothing more complicated than this woman held hands with Jessica and walked her out of the park. She's a very friendly and outgoing girl and perhaps that's the reason why she went with this woman," Pomeroy said.
Jessica, the latest in a string of kidnapped girls to grab the nation's attention, was found safe and unhurt Tuesday.
Jessica was taken to Childrens Hospital, where she was examined, then reunited with her parents, reports CBS News Correspondent Manuel Gallegus.
"The mother, as you might expect, was weeping hysterically and little Jessica threw her arms around her mother and began to laugh hysterically. And then after a few minutes, she also began to weep," Police Chief Martin Pomeroy told reporters Tuesday night.
Authorities were still looking for the man witnesses said they saw walking with Jessica on Sunday night and trying to determine his connection to Cornejo.
Pomeroy speculated that whoever took Jessica from Echo Park "gave up and said, 'I know the police are coming.'"
Jim Mangia, executive director of the St. John's Well Child Center, located about seven miles from Echo Park in a nondescript beige building, said Jessica was brought in by a well-dressed woman in sunglasses who refused to sign the clinic's forms and wrote that the child's name was Maria Ortiz.
Receptionist Denise Leon says she recognized little Jessica Cortez soon after she was brought into the clinic by a woman later identified as Patricia Cornejo.
Leon says Cornejo wanted Jessica examined, but wouldn't answer any questions about her.
Nurse practitioner Denise Hill says she stretched out Jessica's exam, giving officers time to arrive.
Although the woman was well dressed, the little girl was in tatters -- dirty, barefoot and with her hair cut jaggedly. Mangia said a nurse took the pair into an examining room while other clinic staff called police.
"She was wearing shorts and a T-shirt and we immediately went on the Internet to see if it was the same clothing (Jessica was wearing when she disappeared)," Mangia said. "It wasn't, but we thought it is better to be safe than — sorry.
"We assumed that she was a kidnapper given how she was acting."
When the woman went to the bathroom, clinic staff questioned Jessica.
"We went in and spoke to Jessica, asked her her name, she said it was Jessica — the woman had signed in a different name — and then we asked her if that woman was her mom and she said no ... all the time we were waiting for the police," Mangia said.
"When the police arrived, and it was clear that she was safe, we all started to cry with tears of joy. We were just so thankful and so grateful that she came here and we were able to help," Mangia told CBS.
Before the girl was found, police divers had spent hours searching Echo Park's murky lake as hundreds of officers canvassed the neighborhood. The city and FBI offered a total of $45,000 in rewards just hours before the girl was found.
Police had also released a sketch of a man who witnesses said was talking and walking with the girl at the park. Witnesses said the man had a Chihuahua dog.
Jessica, wearing a white dress with pink flowers, was at Echo Park with her parents and brother Sunday when the family noticed she was missing about 7:30 p.m.
Rafael Cortez, the girl's father, and Maria Hernandez, her mother, sell tacos from a small stand across the street. Witnesses said they often let their three children, Jessica, a 5-year-old brother, and a younger sister, play unattended in the park.