US authorities rescued 52 children from prostitution rings and arrested nearly 700 people during a nationwide sting operation over the weekend, the FBI announced Monday.

The three-day push in 36 US cities - led to the recovery of 52 children who were being victimized through prostitution - and the arrest of close to 700 others - including 60 pimps, on state and local charges  the Federal Bureau of Investigation said.

- Child prostitution continues to be a significant problem in our country, as evidenced by the number of children rescued through the continued efforts of our crimes-against-children task forces - said Kevin Perkins, assistant director of the FBI's Criminal Investigative Division.

The roundup, which officials said took place over the previous 72 hours, was part of a larger FBI program called "Innocence Lost," whose task forces have removed nearly 900 children from the streets since 2003, convicted 510 people and seized 3.1 million dollars in assets, the FBI said.