By Jim Williams

CHICAGO (CBS) — The scope of the FBI’s three days sting aimed at the sex trafficking of children was enormous.

Agents and police officers swept through 76 cities, including Chicago. Across the country, they rescued 105 children and arrested 150 pimps.

Law enforcement officials call it an escalating threat as children, some as young as nine, are lured into the sex trade.

“Pimps market and sell children for sex openly at popular online classified sites like Backpage, they sell them at truck stops and they sell on streets in every city in America,” said John Ryan of the Center for Exploited Children.

The sweep included Chicago, where two children were rescued here and one pimp was arrested.

Maureen Blaha of the National Runaway Safeline, which takes calls from children in trouble across the United States, says Americans should not be naive.

“People think about sex trafficking as, oh, maybe Thailand, maybe Mexico, ‘that doesn’t happen in our own backyard’ and indeed it does happen in our own backyard.”

Your image of the scary pimp on the street corner might not be completely accurate.

Blaha says that sometimes “it’s their friend who knows this young person is in a very vulnerable situation.”

Blaha recalls one girl who was convinced to leave her troubled home for Las Vegas.

“Her friend said ‘come and stay with me in Las Vegas’ and it seemed like just the right answer. She got to Vegas and her girlfriend recruited her into the sex trade,” said Blaha.

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