15-year-old Sierra LaMar, in a photo supplied to ABC News.

Authorities say they found the cellphone of 15-year-old Sierra LaMar, a missing California teenager, late Saturday night on the side of a road about a mile away from her home in Morgan Hills, California. Public information officer Sgt. Jose Cordoza of the Santa Clara Sheriff's Office said search and rescue personal found the phone turned off, and they are doing a forensic search for more clues.  The charger for the cell phone was found in her room at home.

LaMar was last reported seen by her mother at 6 a.m. before she left for school last Friday morning. Her mother then left for work and did not actually see Sierra leave the house.

Sierra's father, Steve LaMar, told ABC News he has no reason to believe she was planning on running away. He said there was "nothing out of the ordinary" about her behavior before her disappearance. He spoke to her Thursday evening and she asked him to make an upcoming hair appointment for her.

"I talked to Sierra on the phone Thursday night. She was happy, talking to me about homework. She was asking me to make an appointment so she could dye her hair. She was happy," LaMar told ABC News.

Sgt. Cordoza told ABC News they are strictly regarding this as a missing person case.

"There is no information leading us to believe she purposely ran away. On the other hand we don't have information or evidence associating a crime with her being missing," he told ABC News.

Her family became worried after she didn't return home from school on Friday. They reached out to her friends, thinking she was with one of them. Their concern grew when one friend said Sierra wasn't in class earlier that day. They decided to contact authorities around 5 p.m. on Friday, after her high school sent them an email saying she didn't show up for school at all.

Steve LaMar still lives in Fremont, California, where Sierra lived until October when she moved with her mother and transferred to Sobrata High School in Morgan Hills. The parents are divorced but both have been cooperative throughout the investigation, said police.

Sgt. Cordoza told ABC News they have suspended their search in the areas near her home, and people will no longer be going out due to a lack of evidence. They are focusing their attention on students at both her current high school and the previous school she attended in Freemont.

"We have exhausted our search efforts in that area. We have investigators talking to kids hoping they can lead us in the right direction as far as where she could be. We are looking for any information period," he said.

LaMar is described as being 5 feet 2 with long brown hair, and was last seen with a pink and brown purse.

Sierra's father told ABC News she loves listening to music and used to dance competitively. He said was a cheerleader at her old school and loves being around her friends.

"We are all praying for her to come home and that she is safe. I love her and miss her and we want her home," LaMar told ABC News.