(CHICAGO) More than 200 people were arrested in Cook County during a month-long sting aimed at reducing sex trafficking.

More than 1,300 sex buyers were arrested across 18 states during the National Johns Suppression Initiative, which lasted from July 1 to Aug. 7, the sheriff’s office announced Wednesday.

Cook County Sheriff Tom Dart launched the initiative in 2011, and it now includes the nation’s 10 largest cities.

Cook County had the most arrests with 230, according to thesheriff’s office. One of the arrests was a 15-year-old attempting to buy sex.

Nationwide, 32 underage girls who had been lured into human trafficking were recovered, and there were 71 human trafficking arrests.