Eighteen victims of child pornography were rescued during a nationwide sweep by federal law enforcement agencies, U.S. Immigration and Customs Enforcement announced Friday.

The sweep, dubbed Operation Orion, resulted in the arrests of 190 individuals, most of which were in the U.S. but included arrests in Argentina, the Philippines, Spain and the United Kingdom, ICE said in a press release. The operation took place from May 1 to May 31.

"Let this operation be a warning to anyone who would think they can use the Internet to exploit children: we are out there looking for you, we will find you, and you will be prosecuted," ICE Director John Morton said in a statement.

Morton said as children begin summer vacations, parents should pay extra attention to how much time they spend on the Internet.

"Many of the child exploitation cases under Operation Orion began with a child or teen chatting with someone he or she met online," Morton said in the statement.

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