CAMERON, N.C. — A state Highway Patrol helicopter joined the search Monday for a Harnett County teenager missing for more than a week.

The 17-year-old is mildly mentally retarded and needs medication. She lives with her aunt and uncle in Harnett County. The girl's aunt and uncle say their niece has run away before, but she has never been gone for more than 45 minutes at a time.

They say she was upset when she took off eight days ago with just $5 in her pocket.

"She has a lot of questions [about her parents] that she doesn't understand, and apparently she needed some answers and nobody could give them to her," her uncle said.

With the help of search dogs from Virginia, Harnett County deputies spent the weekend searching for the teen. They found a hat and wash cloth that belong to her along Line Road, which is not far from her home and where her family said she has gone to try to hitchhike in the past.

"We're holding out hope she's safe and sound wherever she is. We have not been able to determine she's still here," Harnett County Sheriff Larry Rollins said.

The girl's mother lives in Jacksonville, Fla. She said investigators believe may be heading there.

The mother she spoke to her daughter by phone after she tried to run away about a month ago.

"She was crying and asking me, 'Mama, why can't I come home? Mama, I want to come home," she said. "It's very hard. I mean my daughter's out there and she needs to be found. She needs to be brought home."

The teenager'sfather lives in western North Carolina.