KRON 4's Rob Fladeboe is watching as the Santa Clara County Sheriff's Office Search and Rescue Unit is deploying about 20 searchers along with three human remains detection canines for the effort.  Later other searchers will check out locations in the Gilroy area.

It's been nearly three weeks since the 15-year old was last seen leaving home for school on March 16th.  Investigators now say they're going on the assumption the girl is the victim of foul play.

Investigators say they continue to monitor a tip line in the case around the clock.  More than 1,000 tips have come in via both phone calls and e-mails.  Detectives say they follow up on all of them.

The FBI and state authorities have also been helping in the search for Sierra.

Stay tuned to KRON 4 and KRON4.com for comprehensive coverage of the search for Sierra Lamar.

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