Police are interviewing registered sex offenders in the area near where a 15-year-old California girl was last seen as she left for school early Friday.

Authorities are questioning the sex crimes offenders who live close to where Sierra LaMar, of Morgan Hill, Calif., disappeared, Fox affiliate KTVU-reported. There are 276 registered sex offenders in the area.

The girl's father, Steve LaMar, who lives some 40 miles away in Fremont, is a registered sex crimes offender but is not considered a suspect in the case, according to the station.

The teen was last seen leaving for school at around 7:15 a.m. Friday morning. Police dogs searching for the girl lost her scent at the driveway of her home, authorities said.

The teenager usually walked from her home to a nearby bus stop, but a bus driver reportedly said he saw no sign of her. She was reported missing by her family Friday evening when they learned she had not attended school. 

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Police found the girl's phone Saturday night about three-quarters of a mile from LaMar's home by tracking its electronic ping. The phone, a Droid smartphone, was discovered about 20 feet from the side of the road that LaMar used to walk to her bus stop.

Authorities are treating her disappearance as a missing persons case, but family and friends of the girl say it's unlikely she ran away. The girl's cellphone charger was also found in her bedroom and her Twitter and Facebook accounts haven't been used since Thursday, leading many to believe she did not plan her disappearance.  

On Wednesday, hundreds gathered at the Morgan Hill Presbyterian church for a candlelight vigil, including the girl's father, who appeared distraught, KTVU reported.

"If you can hear me, just realize how much I love you and want you back," the teen's mother, Marlene LaMar, said at the vigil. 

The girl, a sophomore at Sobrato High School, lives with her mother and stepfather. She transferred to the school in October after the family moved from Fremont to Morgan Hill. Sierra's father, Steve Lamar, lives in Fremont. 

Police say they are also interviewing faculty and friends at both schools for any clues into her whereabouts.  

Sierra LaMar is described as 5-feet, 2 inches tall, with brown hair. She was last seen carrying a Juicy brand pink and black purse. 

Anyone with information on the teenager's whereabouts is being urged to call the Santa Clara County Sheriff's Department at (408) 299-2311.

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