PALOS HILLS, IL -- The National Center for Missing and Exploited Children has issued an alert for a Tinley Park teen who has been missing since Dec. 10. Isis Sicily Zavala, 16, was last seen in Palos Hills, where she had been visiting her grandmother. Her family became concerned when they noticed she was gone the next day.

According to her mother, Kristin Zavala, the family received texts from Isis on Tuesday, Dec. 11, stating she would not be attending her grandmother's birthday party the following day. The teen was expected home last Wednesday. When Isis did not contact her parents on Thursday, they reported her missing to Palos Hills police the morning of Dec. 13. Her mother has been networking with neighborhood Facebook groups in a desperate search to find her daughter. The teen's phone has apparently been turned off, which Kristin said is highly uncharacteristic for her daughter.

Kristin said in a Facebook post that her daughter's case has been entered in the FBI database and Homeland Security is searching "so that [Isis] doesn't leave the state." Isis may be in the company of an older male, possibly in the Hickory Hills or TInley Park area. If seen, her mother asks that members of the public NOT to approach her, out of concern that she may run.

"If you see her do not approach her but follow her, maybe get a license plate number and call [Palos Hills police]," her mother said. Isis is described as a 16-year-old Hispanic female, around 4-feet-11-inches tall, 120 pounds, with black hair and brown eyes. She may be wearing light colored ripped jeans, a black sweater, and a pink fluffy jacket.

If you know of Isis's whereabouts, contact the Palos Hills Police Department at 708-598-2151 or call 911.