CHICAGO (STMW) — The Cook County Sheriff’s Police told them they were coming.

The agency took an ad out on Backpage.com and warned it was “investigating and arresting” human sex traffickers and those who enable them by answering escort ads.

“They still did it,” Sheriff Tom Dart said Monday at his headquarters in Maywood. “We knew they would.”

So in the week leading up to the Super Bowl, Dart said his officers worked with suburban police departments on an online prostitution sting that netted more than 60 arrests across Cook County. Broadview, Lansing and Matteson also helped locally, Dart said, while a national sting caught just under 600 people.

Most of the people arrested were accused of trying to hire prostitutes online, the sheriff said. Officers posted fake ads, made arrangements to meet at hotel rooms with people who responded and arrested them after they arrived, he said.

But Dart also said they’ve made those arrests “over and over and over again.” So, he used a Monday morning news conference with U.S. Sen. Mark Kirk, R-Ill., to attack the website that allegedly facilitated the prostitution: Backpage.com. Dart said it’s filled with ads for prostitution.

“Let’s be clear here,” Dart said. “There’s nothing else on their site there. There’s no massages. There’s no nothing.”

In an emailed statement, Liz McDougall, general counsel for Backpage.com, wrote: “Backpage.com is a general online classified advertising website with millions of ads for jobs, real estate and items for sale. Ads posted in the ‘adult’ category constitute less than 10% of the site’s overall ad content. Sheriff Dart’s conflicting portrayal of the site content is erroneous.”

Dart said Backpage.com cannot be held responsible under existing law for the advertisements its customers post. But Kirk said he’s pushing a bill with the help of U.S. Sen. Dianne Feinstein, D-Calif., that could hold the site liable for content its users post.

Kirk said he’s optimistic about the bill’s chances because of his bipartisan coalition with Feinstein. However, Kirk has already been pushing such legislation for nearly a year.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2015. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)