PHOENIX — Police in Surprise partnered with federal and local law enforcement agencies across the Valley to arrest 21 men in a recent child sex trafficking operation, authorities said Wednesday.

As part of the sting, dubbed Operation Back to Skool, undercover detectives placed ads on websites where suspects are known to seek illegal sex acts, the Surprise Police Department said in a press release.

The suspects, who were booked on a variety of counts, ranged in age from 23 to 62.

The alleged crimes included attempted sexual conduct with a minor and child sex trafficking.

Homeland Security Investigations, the U.S. Marshals Service, the Maricopa County Attorney’s Office and police from Scottsdale, Goodyear, Peoria and Glendale joined the Surprise Police Department Criminal Investigations Division for the operation.

Surprise Police made 15 of the arrests, and the Scottsdale Police made the other six.

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