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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Sierra LaMar, 15, vanished after leaving her Morgan Hills, Calif. home on March 16 and headed for school.
Police found LaMar's cellphone on Saturday, March 17 -- the day after she was last seen. Cops said they're searching her phone records for clues.
LaMar was a cheerleader in high school before moving to a new town, Morgan Hill, with her mother in October. Her parents are divorced and police said that both were cooperating with the investigation.
Police are treating LaMar's disappearance as a missing person case. Her parents insist it's unlikely that she ran away.
LaMar is 5-feet-2-inches tall with a thin frame. She was carrying a pink and black Juicy purse when she left home.
Anyone with information about LaMar may contact the Santa Clara County Sheriff's Office at (408) 299-2311
Deputy Peter Robinson, of the Santa Clara County Sheriff Underwater Search Unit, surveys a pond on Tuesday, April 17, 2012 in Morgan Hill, Calif. The search for missing 15-year-old Northern California girl expanded on Tuesday as investigators followed new leads one month since her disappearance. The Santa Clara County Sheriff's office would not say what the new leads were in the case of Sierra LaMar, except that they came from evidence already collected. The teen was seen leaving her Morgan Hill home on March 16. (AP Photo/Marcio Jose Sanchez)
A sign with a photo of missing teen Sierra LaMar is posted at an intersection on Tuesday, April 17, 2012 in Morgan Hill, Calif. The search for missing 15-year-old Northern California girl expanded on Tuesday as investigators followed new leads one month since her disappearance. The Santa Clara County Sheriff's office would not say what the new leads were in the case of Sierra LaMar, except that they came from evidence already collected. The teen was seen leaving her Morgan Hill home on March 16. (AP Photo/Marcio Jose Sanchez)
The Santa Clara County Sheriffs underwater search unit prepares to lower a zodiac into Calero Reservoir to look for clues in the disappearance of missing teenage girl Sierra LaMar Tuesday, March 27, 2012, in Morgan Hill, Calif. LaMar disappeared as she headed out for school on March 16, and her cellphone and bag were found tossed in two separate locations shortly after. (AP Photo/Ben Margot)
HOLD FOR STORY: In this photo from Monday, March 26, 2012, posters bearing images of missing teen Sierra LaMar are seen at Burnett Elementary School in Morgan Hill, Calif. LaMar disappeared as she headed out for school on March 16, and her cellphone and bag were found tossed in two separate locations shortly after. (AP Photo/Ben Margot)
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.