Four men arrested on suspicion of pimping in Sonoma County during a national effort targeting child prostitution were from Sacramento, Oakland and Vallejo, authorities said.
Only one of the three teenage girls suspected to have been working in prostitution whom officers rescued during operations in Santa Rosa and Petaluma was a local resident, Sonoma County Sheriff's officials said.
The other two girls were from elsewhere in Northern California. They were ages 15 to 17.
The regional span of people involved in underage prostitution at local hotels illustrates the movement of pimps and child prostitutes throughout the Bay Area, said Sgt. Ruben Martinez, who runs the Sheriff's Office domestic violence/sex crimes team.
"There is a circuit," Martinez said.
"They move around, and they say where they'll go," Santa Rosa Police Sgt. Terry Anderson said.
Erotic advertisements on websites often include a range of locations where a prostitute might work.
Officers combed websites trying to identify girls who looked underage. Detectives don't just rely on appearance; they also look for other signs such as key words often used to hint to a potential customer seeking out juveniles, Anderson said.
"Child prostitution is not visible on the street anymore; they're using social networks," District Attorney Jill Ravitch said.
Over the past two years, law enforcement agencies have referred 18 human trafficking cases to the District Attorney's Office, Ravitch said.