MORGAN HILL (CBS 5) — The search for missing teen Sierra LaMar took crime scene investigators to a barren hillside between San Jose and Morgan Hill on Friday.

Working under pop-up tents, investigators poured five-gallon buckets of soil through a sifter, to capture small pieces of potential evidence.

A Santa Clara County Sheriff’s spokesperson told CBS 5 a volunteer search crew alerted them to something suspicious on the hillside. After several hours, investigators left the area but did not say if any clues were found.

LaMar, a 15-year-old sophomore at Ann Sobrato High School, was last seen on the morning of March 16th. Sheriff’s officials have classified the case as an abduction.

Investigators have only found her cellphone and her purse, which contained a pair of pants and a t-shirt belonging to the teen.

KCBS’ Anna Duckworth Reports:

Volunteers continued their search for LaMar on Friday. One team concentrated on a field in rural Morgan Hill where an empty handcuff box and used condoms were found on Thursday. The evidence has been sent to a crime lab to determine if the items are connected to LaMar’s disappearance.

Searchers have also looked at nearby waterways.

Around 700 volunteers took part in Friday’s search, while more than 2,000 have taken part so far this week. The search for LaMar will continue this weekend on the Coyote Creek Trail, with deputies on ATVs.

On Saturday, state Assemblyman Luis Alejo, D-Salinas, will join volunteers conducting the ground search.

Detectives continue to investigate more than 720 tips related to the case sent to the sheriff’s office via phone or email, Cardoza said.

The teen’s classmates at Ann Sobrato High School have established a reward fund for Sierra’s safe return and placed a donation box in the school’s front office.

Checks can be made payable to Ann Sobrato High School ASB and mailed or dropped off at the school, located at 401 Burnett Ave.

The KlaasKids Foundation has also established a fund to help in the search. To contribute to the fund a link is available at Facebook.com/find.sierra.lamar or contributions can be made directly to the Sierra LaMar Fund at any Chase bank.

Donations of food, water bottles, office supplies or money are also welcome, according to KlaasKids.

Those interested in volunteering in the search-and-rescue efforts are asked to register at Burnett Elementary School, located 85 Tilton Ave., between 8 a.m. and 1 p.m. through Sunday. Volunteers must be at least 18 years old and bring a photo ID.

On Saturday, however, a Teen Brigade will be organized starting at 8 a.m. A youth walk will also take place at 11:30 a.m. at the Community Center at Dunn and Monterey streets.

Anyone with information about the case is asked to call sheriff’s investigators at (408) 808-4500 or the anonymous tip line at (408) 808-4431. Tips can also be emailed to tips@sheriff.sccgov.org.

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