Last Friday, 15-year-old Sierra LaMar disappeared from the driveway of her home and was never seen again. The next day, her cell phone was discovered on the side of the road. It's possible that the phone was thrown from a moving vehicle. The California teen, who lived and went to school in Morgan Hill, is likely the victim of an abduction.

Police have questioned registered sex offenders in the area as well as searching her phone records and laptop. So far, there are no clues to her whereabouts. Investigators have even studied her social media activity, since it is common for predators to lure young women via Facebook and other popular sites. Aside from her 6:30 a.m. Tweet to a friend, no evidence has emerged suggesting that she was in contact with the person(s) responsible for her disappearance.

Over 150 tips have come in but have not brought authorities any closer to uncovering the mystery of what happened to LaMar. Police are asking for anyone with information on the case to contact them immediately. Sierra LaMar is 5'2 tall and thin with brown eyes and long black hair. Call in tips to Santa Clara Sheriff's Department anonymous tipline at (408) 808-4431. A Facebook page was, Help Find Sierra been created to aid the search.