By Joe Johns and Tom Cohen
WASHINGTON (CNN) -- In what it called its largest crackdown to date on child prostitution, the FBI announced Monday that a nationwide operation over the weekend resulted in 150 arrests, with 105 children rescued.
Authorities said the operation, which took investigators to race tracks and truck stops, also targeted the use of social media sites for child prostitution activity.
Overall, the three-day undercover roundup Operation Cross Country took place in 76 cities and involved 230 law enforcement units, according to the FBI.
"Child prostitution remains a persistent threat to children across America," said Ron Hosko, assistant director of the FBI's Criminal Investigative Division. "This operation serves as a reminder that these abhorrent crimes can happen anywhere and that the FBI remains committed to stopping this cycle of victimization and holding the criminals who profit from this exploitation accountable."
He said at a news conference that a prime environment for child prostitution is major sporting events such as the Super Bowl, where authorities had "multiple recovery of children" in the past.
The operation was the largest sweep to date in the FBI's Innocence Lost National Initiative, according to Hosko.
It included 28 searches with 129 seizures of cash, drugs, vehicles and firearms, he said, and those arrested face a variety of charges, including pimping.
The ages of children rescued in this, the seventh iteration of Operation Cross Country ranged from 13 to 17, Hosko said.
He credited the increased success of the latest operation in part to an expansion of the probe to websites such as www.backpage.com, which he called a forum "where pimps and exploiters gather."
"It appears as though we were 30% to 40% more successful in identifying both victims and pimps in this operation," Hosko said.
A goal of the Innocence Lost initiative is to identify children lured or forced into prostitution and remove them from risk, Hosko said. The circumstances of the situation, often involving young girls from broken homes, make finding them especially difficult, he explained.
"Commonly some of these children have stepped away from their families," he said, adding that "there is no one to call and report 'my daughter is missing.'"
Another major problem is the culture of abuse, both physical and emotional, as well as drug use prevalent in child prostitution.
"We have victims whose new normal is abuse and is drug-infected, then the expectation of somebody who cares about them may last for 30 minutes or an hour before the abuse starts again," Hosko said. "So that makes our job more difficult."
CNN's Virginia Nicolaidis and Bill Mears contributed to this report
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