Authorities investigating the case of missing California teenager Sierra LaMar have arrested five sex offenders.
The arrests come after authorities interviewed nearly 300 sex offenders in regard to the teen's unsolved disappearance.
"As a result of contacting ... sex offender registrants, for information in the Sierra LaMar case, the Sheriff's Office Sexual Assault Felony Enforcement Task Force has arrested five separate persons, and is investigating several others," said Sgt. Jose Cardoza, a spokesman for the Santa Clara County Office of the Sheriff.
According to Cardoza, the men were arrested for violating sex offender registration requirements.
LaMar was last seen around 6 a.m. March 16, when she left her Morgan Hill home in Santa Clara County to attend classes at Sobrato High School. The sophomore never made it to the bus or school. Her mother learned LaMar was missing when she got a message from the school's automated attendance system at 6 p.m., police said.
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On March 17, authorities found Lamar's cellphone discarded along a road roughly three-quarters of a mile northwest of her mother's home. The condition of the phone indicates it may have been tossed from a vehicle.
The following day, the sheriff's office found a purse and a backpack containing LaMar's clothing in a location about 2 miles in the opposite direction of her bus stop -- and a mile from where investigators recovered her cellphone.
Forensic examinations of the items have not revealed any new leads.
Because LaMar does not have a history of running away and has a close relationship with her family, authorities suspect she might have been abducted. Still, police have no suspects and no persons of interest at this time.
So far authorities have investigated more than 1,600 tips.
The Sheriff's Dive Team plans to resume water searches this week in the southern Santa Clara County area. Investigators will use side scan sonar, which detects objects below the surface levels, to identify areas of interest and will then send divers in to investigate.
"Parkway Lakes in south San Jose will be checked early this week, followed by Anderson and Coyote reservoirs," Cardoza said. "Almaden and Guadalupe reservoirs also in south San Jose, will be checked later this week."
Sierra LaMar is 5 feet 2 inches tall with a thin build. She has brown eyes and long, black hair, and was last seen with a Juicy brand purse with a black and pink design.
Anyone with information on this case is asked to contact the sheriff's department at 408-808-4500 or the anonymous tip line at 408-808-4431. Email tips can be sent to firstname.lastname@example.org.