MORGAN HILL . (AP) — Nearly a week after a 15-year-old Northern California girl disappeared on her way to school, family members and friends remained baffled about what happened to her.

Authorities disclosed Thursday that they had found Sierra LaMar's purse a few miles from her home on Sunday but saw no signs of foul play and were still treating her as a missing person, not a runaway.

"We're looking for any evidence of a crime — clothing, weapons, tire tracks, anything suspicious that could help out in the investigation," Santa Clara County sheriff's Sgt. Jose Cardoza said.

Meanwhile, search crews fanned out over a three-mile radius near the girl's home in Morgan Hill, a suburb of San Jose.

The teen was last seen at home getting ready for school last Friday. With the exception of sending a normal text message to a friend, she hasn't been heard from since.

As many as 75 officers have been working the case and more than 150 tips have poured in as family and friends frantically passed out fliers with an image of Sierra's smiling face. Candlelight vigils have helped loved ones hold out hope that she returns safely.

"Each day it gets more real," Sierra's mother, Marlene LaMar, said during a vigil Wednesday in nearby Fremont. "It's been six days and it feels like forever."

On Thursday, Cardoza said searchers found Sierra's pink-and-black Juicy brand purse about two miles from her home.

Inside was a neatly folded pair of pants and a T-shirt, said Cardoza, adding that authorities did not initially release the information until they could confirm it belonged to the girl.

He said police weren't sure if Sierra was wearing the clothes found in the bag at the time of her disappearance or if she was carrying an extra set of clothing.

It's the second item found that belonged to Sierra. On Saturday, searchers found her Samsung Galaxy cell phone on the side of a road less than a mile from her home.

Investigators have also contacted dozens of registered sex offenders living in the area.

Sierra's father, Steve Wayne LaMar of Fremont, is a registered sex offender. He has been cooperating with authorities and is not considered a person of interest in his daughter's disappearance.

He pleaded no contest in 2009 to lewd acts with a minor younger than 14.

"I understand the stigma associated with this in my background, and I assure everyone it is not connected in any way to my daughter's disappearance," Steve LaMar said in a statement on Wednesday. "I ask that you please not shift the focus away from the investigation and from finding Sierra."

Another vigil is scheduled Friday, a week after her disappearance.

"The more days that pass, obviously the harder it is to handle," her sister Danielle LaMar told the San Jose Mercury News.