Police say the 30-year-old woman sent a message to her brother in Florida saying she was being held against her will.
New Jersey police think 29-year-old Trenace McCarroll bailed out a woman from jail and then essentially kidnapped her and worked her as a prostitute to pay off the bail money.
He thought the woman had no cell service, but she had an iPhone that got a Wi-Fi signal.
She used it to put out a call for help on Facebook to her family, who called Hackensack Police, who then went to McCarroll's apartment. They didn't find him, but he later turned himself in to the police station with the woman in the car.
The police chief says she might still be a sex slave if it wasn't for her iPhone and Facebook.
"It had no service, so I think that he was under the impression that she couldn't do anything with it, but as we all know, these new phones you have Wi-Fi access and there's a lot of Wi-Fi spots," said Captain Tomas Padilla, Hackensack Police Department.
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