SAN DIEGO — Brent and Kelly King knew something was wrong when they discovered their 17-year-old daughter Chelsea wasn't home.
They called her cell phone then her friends. They tried an AT&T Web site and learned her phone had been left inside her 1994 BMW in Rancho Bernardo Community Park, a giant, wooded area on the northern edge of San Diego.
"Because it was so out of character for Chelsea not to tell us or call us and say I'm going to be late ... we just had that feeling," Brent King recalled Monday, four days after the disappearance of his daughter.
Kelly King called 911 as her husband drove to the park. He found his daughter's belongings inside her car then spotted a running trail into the woods.
"I took off and ran down the trail as far as I could run, calling out for my daughter at the top of my voice in every direction," he said, explaining his daughter is an avid runner.
A massive search was under way for Chelsea King, as authorities questioned a registered sex offender arrested Sunday for investigation of her murder and rape.
Sex offender in custody
John Gardner III, 30, remained in custody without bail after his arrest outside a Mexican restaurant in suburban Escondido. Steve Walker, a spokesman for the district attorney's office, said a decision would be made by Wednesday about filing charges against Gardner.
Sheriff Bill Gore said physical evidence recovered during the search linked Gardner to the disappearance, but he declined to elaborate.
Gore said on ABC's "Good Morning that the interrogation of Gardner had not been productive.
"We questioned Mr. Gardner into the evening and so far we still don't know where Chelsea is," Gore said. "We're confident that we have the right man in custody. Now we've just got to find Chelsea."
About 100 agents searched a rugged, four-square-mile area of the park on Monday. The FBI's Los Angeles office also brought sonar equipment to search Lake Hodges and 14 miles of shoreline.
"The terrain is tricky out there," said Jan Caldwell, spokeswoman for the San Diego County Sheriff's Department. "They're going slowly for the safety but also slowly to make sure they cover every single square inch."
Authorities also searched Gardner's home in Lake Elsinore and his mother's home in San Diego, Caldwell said. She declined to comment on what, if any evidence, the searches produced.
King's parents said they last saw Chelsea when she went to bed about 9:30 p.m. Wednesday after playing French horn in a school concert. On the way home, they had mailed an application for financial aid at Boston University, one of 11 colleges where Chelsea applied.
Running was her outlet
The parents heard Chelsea leave the house at 6:15 a.m. Thursday for a peer counseling commitment. But she wasn't home at 5:30 p.m., when Brent King returned from the gym and his wife got home with groceries.
They described their daughter as a straight-A student who plays French horn for the San Diego Youth Symphony. At suburban Poway High School, Chelsea runs on the cross-country team.
"That was her outlet when she was stressed about a test or needed to just clear her head," Kelly King said.
Chelsea was born in Poway, a well-to-do suburb of homes and office parks northeast of San Diego. Her family, including her 13-year-old brother, had followed Brent King to various mortgage banking jobs in the San Francisco Bay area and suburban Chicago before returning to the San Diego area.
Their home was badly damaged in 2007 wildfires that ravaged Southern California. Brent, 47, is now between jobs. Kelly, 48, works as a medical assistant in dermatologist's office.
Chelsea researched 90 colleges, with an eye toward a career that would combine her interests in writing and environmental protection. She has been accepted by two schools, the University of Washington and the University of British Columbia.
"She is one of the most driven, personable, caring people that you could ever meet," Brent King said. "Her goal in life is to brighten everyone's day. That's what she does, and when she walks into the room, you know she's there."
Investigators also suspect Gardner could be tied to a Dec. 27 assault on a female jogger from Colorado who fended off her attacker in the same park.
Convicted in May 2000
Gardner, a resident of Lake Elsinore, about 75 miles north of Poway, was required to register as a sex offender because of a conviction for lewd or lascivious acts with a child under 14, the Megan's Law Web site said.
He was convicted in May 2000 of molesting a 13-year-old female neighbor and sentenced to six years in prison. A psychiatrist who interviewed Gardner said he showed no remorse for his actions. according to the court records obtained by the newspaper.
"There is no known treatment for an individual that sexually assaults girls and does not admit to it in any way," Dr. Matthew Carroll said in the documents.
At Poway High School, students and staff members wore blue shirts to represent the color of the teen's eyes and tied blue ribbons around campus light poles.
Principal Scott Fisher thanked students for their search efforts, echoing King's parents, who said the massive effort by law enforcement and volunteers was sustaining their spirits.
"Without that, it would be really, really unbearable," Brent King said.
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