By Louisa Moller, WBZ-TV

BOSTON (CBS) – Massachusetts film director, Mary Mazzio, says she was astounded to learn that child sex trafficking is happening in the United States.

“When I first read this article I thought, child sex trafficking? That doesn’t happen in this country,” Mazzio said.

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The troubling realization inspired her to create a movie highlighting the issue. Called “I Am Jane Doe”, it is now playing in theaters.

“We are talking about hundreds of thousands of children,” Mazzio said.

The film chronicles the stories of child sex trafficking victims, including three “Jane Does” from Boston, who sued Backpage.com for damages after they claimed the website advertised sex with kids.

The movie follows their legal battles and a U.S. Senate investigation into Backpage.com.

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Most importantly, Mazzio says, the film gives voice to the victims and their mothers.

“This became their journey. This became a way to elevate their voices,” Mazzio said.

Mazzio hopes audiences will come away with a new awareness of the troubling problem. She also hopes it will spur a change in the law.

“The law has been protecting the website owners that have made millions of dollars off these kinds of ads. The law simply has to be changed,” Mazzio said.

As a result of the Senate investigation, Backpage.com removed the adult section of its website and called itself the victim of censorship.

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The Jane Doe lawsuits against Backpage.com have been largely unsuccessful.