(CBS) –Senator Mark Kirk said Monday he and Democratic Senator Diane Feinstein have introduced legislation to further crackdown on people involved in human trafficking.

He says the SAVE Act would close loopholes in the Communications Decency Act that Cook County Sheriff Tom Dart says allows human traffickers to “hide behind the Internet” to use women and children in the sex trade.

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The two held a news conference Monday morning at Cook County Jail. Marion Hatcher, a convicted felon and sex trafficking victim, joined Kirk and Dart, her new boss, at the announcement.

“It was just waiting for men and women to knock on the door and come for sex,” said Hatcher.

Getting arrested saved Marion from that life.

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The target of Kirk’s ire against human trafficking is particularly aimed at Backpage.com which, he says, advertises prostitution under the guise of legal activity.

Sheriff Dart says his office has made hundreds of prostitution arrests in the past few years by following up ads on Backpage.com. He says sex trafficking in the age of the internet is only getting more popular.

“After Craigslist became responsible and shut down, Backpage now is the leader,” said Dart.

State’s Attorney Anita Alvarez announced Monday that 10 people plead guilty to sex trafficking after investigators tapped their phones. It’s the first case of its kind in the nation.

“We would not have been able to try a case in this manner. We would have expected these young woman to testify against these guys which I think we can all understand why that wasn’t an easy thing to do and many times they refuse to testify,” said Alvarez.

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Alvarez called the investigation “Little Girl Lost.” Some of the victims were as young as 13 years old.