LOS ANGELES (CBS) — Los Angeles County is one of the “major hubs for sex trafficking” in the U.S., according to a report released Tuesday.

As many as 84 percent of children arrested for prostitution in Los Angeles County live mostly in Long Beach and the South Bay, according to data from the Probation Department.

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“Sadly, this county is recognized as one of the major hubs for sex trafficking in the nation, primarily of girls as young as 11 and 12 years old,” Supervisor Don Knabe said. “Untold numbers of these children fall victim to predatory adults who sexually exploit them for personal gain and often abuse them in unspeakable and brutal ways.”

Knabe thanked Probation Department staffers for their work in helping get a $1 million federal grant to spend on countering sex traffickers.

Chief Probation Officer Jerry Powers said the department had identified 175 young girls as victims of sex trafficking over the past two years.

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“In a county of 10 million, I can tell you that we’re just scratching the surface,” Powers said. He added that about 50 percent of current Los Angeles County probationers with arrests for prostitution began selling their bodies as juveniles, on average between the ages of 12 and 14.

“We think these numbers are representative of a much larger number of girls forced into prostitution who have not yet been arrested, or are not being determined to be sexual victims in screenings when placed in either foster care or the juvenile justice system,” Knabe said. “It’s the biggest problem we have on this issue — we don’t know what we don’t know.”

The board declared January “National Human Trafficking Awareness Month” and told staffers to track and gather more statistics to develop a strategy for fighting child prostitution. The county also will consider dedicating a unit within the Probation Department to sexually exploited minors.

“These young girls have often suffered in their own homes and then move to a life on the streets where they are further victimized by local pimps and gangs,” Knabe said. “As a grandfather, it is horrifying to think of the lives these young girls face.”

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