Dutch prosecutors say police have arrested 33 suspected child molesters worldwide, including 8 in the United States, using information gathered from the computers of a pedophile in Amsterdam who abused dozens of babies and toddlers.

Robert Mikelsons, a Latvian-born Dutch citizen, was sentenced to 18 years in prison on May 21. Dutch prosecutors said Wednesday Mikelsons provided thousands of leads, resulting in 13 arrests in the Netherlands, eight in the U.S., six in Canada, four in Britain, and one each in Germany and Sweden. John Morton, who heads the investigative arm of the U.S. Department of Homeland Security, praised the cooperation, saying it saved 138 children from ongoing abuse.

Mikelsons was himself caught in 2010 on a tip from U.S. authorities investigating a Massachusetts man who faces sentencing next month.