The FBI says more than 600 people have been arrested and 47 children rescued in a three-day roundup targeting people who force children into prostitution.

The arrests by federal, state and local law enforcement took place in 29 cities as part of Operation Cross Country II.

At a news conference Monday, FBI Deputy Director John Pistole said the arrests were made possible by intelligence gathered during a similar series of raids in June.

The 47 rescued children ranged in age from 13 to 17. A total of 642 people were arrested. The FBI says they include 73 pimps and 518 adult prostitutes. The bureau said that it also dismantled a dozen large-scale prostitution operations that were run through call services, truck stops, casinos and Web sites.