A 15-year-old Pennsylvania girl who vanished 11 days ago is possibly being held against her will, according to reports.

Riley Harkins reportedly left Media on September 21 with a 15-year-old friend, and the latest credible tip last placed her at the SEPTA train station in Bristol. KYW-TV reported that  the friend was located a couple of days after leaving Media. The friend told police that they were taken to a home in the Kingsessing section of Southwest Philadelphia.

An investigation reportedly uncovered that the two 15-year-olds took a train ride into Philadelphia and met up with two people who are older. Police sources told the news station that Harkins—who has been deemed endangered—is possibly being held captive.

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Authorities, who initially deemed Harkins a juvenile runaway, said the teen left without money.

According to Patch, Harkins was described as being 5 feet 2 inches tall, weighing 90 pounds, and having brown hair and blue eyes.

Anyone with information regarding Riley Harkins’ whereabouts should call Media police at 610-565-6656 or the Delaware County CID at 610-891-4717.

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[Featured image: Media Borough Police Department]