Denise Huskins' father, Mike Huskins, said his daughter called him around 9:30 a.m. to say she'd been dropped off at her mother's house in Huntington Beach.
An emotional Mike Huskins told The Associated Press his daughter found no one home there, so she walked 12 blocks to his house, where a neighbour met her and called 911. Mike Huskins and his ex-wife had gone to Vallejo, northeast of San Francisco, as authorities searched for their daughter, 29.
Her safe return capped a bizarre ordeal that began Monday when her boyfriend told police she was forcefully taken from their Vallejo home in the middle of the night and the intruders demanded a ransom.
On Tuesday, the San Francisco Chronicle received an email from an anonymous person claiming to be holding Denise Huskins.
The person wrote that Denise Huskins would be returned safely Wednesday.
"We will send a link to her location after she has been dropped off. She will be in good health and safe while she waits," the person wrote. "Any advance on us or our associates will create a dangerous situation for Denise. Wait until she is recovered and then proceed how you will. We will be ready."
The email included an audio file of a woman identifying herself as Denise Huskins, who mentioned Tuesday's airliner crash in the French Alps to verify she was alive, the Chronicle said. Mike Huskins confirmed the voice in the file was his daughter's, the newspaper reported.
Mike Huskins said Wednesday his daughter seemed calm when he spoke to her but provided few details about what happened.
"She wasn't crying at all. She just said, "Daddy, I'm OK," he said.
The father added he's been unable to get any additional details because his daughter was still speaking with police.
Denise Huskins' boyfriend, Aaron Quinn, called police at about 2 p.m. Monday to report that she was abducted from the Mare Island home they share in Vallejo, about 400 miles north of Huntington Beach.
It's unclear why Quinn, 30, took so long to alert authorities.
A car registered to him was taken from the couple's home and found at an undisclosed location, investigators said.
Police wouldn't reveal further details about the case but said Quinn was not a person of interest.
Mike Huskins said he didn't know anything about a ransom but had no doubt his daughter was kidnapped.
He said he was not headed back to Huntington Beach because Vallejo police still wanted to speak with him.
Denise Huskins works as a physical therapist at Kaiser Permanente Medical Center in Vallejo. She moved to Vallejo in June from Southern California.